terpsfan101 Codes (Mostly Genesis)

[terpsfan101]

Maui Mallard in Cold Shadow (USA) (SNES)

7E1F55:?? Cheat Modifier

00: Disable all Cheats
02: Enable Level Skip Cheat (Press Select + Y + A during gameplay)
04: Enable Infinite Lives Cheat
06: Enable Level Skip and Infinite Lives Cheats
40: Enable Water is Harmless Cheat
42: Enable Level Skip and Water is Harmless Cheats
44: Enable Infinite Lives and Water is Harmless Cheats
46: Enable Level Skip, Infinite Lives, and Water is Harmless Cheats
80: Enable Infinite Health Cheat (Health reaches 0, but you won't die)
82: Enable Level Skip and Infinite Health Cheats
84: Enable Infinite Lives and Infinite Health Cheats
86: Enable Level Skip, Infinite Lives, and Infinite Health Cheats
C6: Enable Level Skip, Infinite Lives, Water is Harmless, and Infinite Health Cheats

[terpsfan101]

King of Dragons (USA) (SNES)

7E5C70:01 Enable 2-Player Same Character Cheat

[terpsfan101]

Battletoads-Double Dragon (USA) (SNES)

7E00FD:10 Enable Mega Warp Zone (Level Select) and 10 Lives Cheat after Character Select Screen

[terpsfan101]

Here's another Master System/Game Gear batch of codes. I'll slowly be adding them to the database

New Zealand Story, The (Europe) (Master System)

00DE12:00 Weapon Modifier - Bow & Arrow (Default Weapon)
00DE12:01 Weapon Modifier - Bombs
00DE12:02 Weapon Modifier - Laser
00DE12:03 Weapon Modifier - Fireball

Sagaia (Europe) (Master System)

00C03F:09 Infinite Credits
3A7-62B-2A2 Infinite Lives
3A1-F94-2A2 Infinite Credits

Super Space Invaders (USA, Europe) (Game Gear)

7E9-66E-3B7 Invincibility (enable before start of level or after dying)
3A7-44E-2A2 Infinite Shields (except when stomped)
3AA-61C-2A2 Infinite Credits
00C7F9:35 Invincibility
00C7ED:02 Infinite Credits

Super Space Invaders (Europe) (Master System)

7EA-71E-3B7 Invincibility (enable before start of level or after dying) - Both Players
3A8-4FE-2A2 P1 Infinite Shield
002-FCA-3BE P1 Infinite Lives
3A8-D3E-2A2 P2 Infinite Shield
3A8-B2E-2A2 P2 Infinite Lives

Chuck Rock (Europe) (Master System)

00C00A:9A Enable Infinite Health and Level Skip Cheats (Press 2 on Controller 2 to Skip Levels)
B6A-5DD-3BE Infinite Health

Chuck Rock (World) (Game Gear)
Chuck Rock (World) (Beta) (Game Gear)

00C00A:9A Enable Infinite Health and Level Skip Cheats (Press Start to Skip Levels) (Disables Pause Button)

Chuck Rock II - Son of Chuck (Europe) (Master System)

3AB-17A-2A2 Infinite Health

Chuck Rock II - Son of Chuck (USA) (Game Gear)

00E-48E-3B4 Invincibility to Enemies

credit: mezmorize

Chuck Rock II - Son of Chuck (Europe) (Game Gear)

00E-9BE-3B4 Invincibility to Enemies
000-74A-19E Infinite Health
000-C4A-19E Infinite Lives

credit: mezmorize

Yu Yu Hakusho 2 - Gekitou! Nanakyou no Tatakai (Japan) (Game Gear)
Yu Yu Hakusho 2 - Battle of the 7 Fighters (Japan) [T-En by Gaijin Productions v1.00] [n] (Game Gear)

00C0A8:04 Unlock Bosses in Vs Mode (You can select them even though they are X'd out)

Sega-Galaga (Japan) (16kB) (SG-1000)

3A5-BCC-2A2 Infinite Lives - Both Players
00C346:09 Infinite Lives - Both Players

Sega-Galaga (Japan) (40kB) (SG-1000)

3A7-AA6-2A2 Infinite Lives - Both Players
00C346:09 Infinite Lives - Both Players

Space Invaders (Japan) (SG-1000)

00C0C2:03 Infinite Lives - Both Players

James Pond 3 - Operation Starfi5h (Europe) (Game Gear)

00D033:FF Enable all Levels on Map (Enable on Title Screen)
00D030:FF Enable Invincibility Cheat
00D030:00 Disable Invincibility Cheat
00D032:FF Enable Infinite Lives Cheat
00D032:00 Disable Infinite Lives Cheat
04E-F2E-E66 Start with 4 Health Units, instead of 3
05E-F2E-E66 Start with 5 Health Units
06E-F2E-E66 Start with 6 Health Units
059-D38-E66 Start with 5 Lives, instead of 3
079-D38-E66 Start with 7 Lives
099-D38-E66 Start with 9 Lives

Super Off Road (USA, Europe) (Game Gear)

00B-86E-3BE Infinite Credits
03F-1BC-E62 Start with 3 Credits, instead of 2
05F-1BC-E62 Start with 5 Credits
07F-1BC-E62 Start with 7 Credits
09F-1BC-E62 Start with 9 Credits

Sonic Drift 2 (Japan, USA) (Game Gear)

7E5-439-3BA CPU Always on same Lap
7E9-B6C-3BA P1 Always on same Lap
00D748:63 Infinite Points
00C349:03 P1 Always on Final Lap
00C349:00 P1 Always on 1st Lap
00C3C9:00 P2 Always on 1st Lap
00C449:00 P3 Always on 1st Lap
00C4C9:00 P4 Always on 1st Lap
00C36D:00 Item Modifier - None
00C36D:01 Item Modifier - Speed Boost (Press up to use)
00C36D:02 Item Modifier - Spring (Press up to use)
00C36D:03 Item Modifier - Mine (Press up to use)
00C36D:04 Item Modifier - Invincibility (Press up to use)

Star Wars (Europe) (Master System)

3AF-3DB-2A2 Infinite Health
3A0-6B9-2A2 Infinite Lives
3A0-8A9-2A2 Infinite Continues

Super Off Road (Europe) (Master System)

004-0EC-3BE Infinite Nitros - Both Players
00D-34E-3BE Infinite Credits - Both Players
7E1-F4B-3B7 Infinite Money - Both Players
05F-2BC-E62 Start with 5 Credits, instead of 2 - Both Players
09F-2BC-E62 Start with 9 Credits - Both Players
19F-2BC-E62 Start with 25 Credits - Both Players
32F-2BC-E62 Start with 50 Credits - Both Players
4BF-2BC-E62 Start with 75 Credits - Both Players
63F-2BC-E62 Start with 99 Credits - Both Players

Captain Silver (USA) (Master System)

7EA-BFE-3B7 Infinite Lives
C99-2DF-E62 Infinite Time

Captain Silver (Japan, Europe) (Master System)

7E1-FAD-3B7 Infinite Lives
0AE-19F-E62 Infinite Time

Michael Jackson's Moonwalker (USA, Europe) (Master System)

3AC-8EC-2A2 Infinite Health
B67-EBF-3BE Infinite Lives
049-EBF-E66 Start with 3 Lives, instead of 2
069-EBF-E66 Start with 5 Lives
089-EBF-E66 Start with 7 Lives
0A9-EBF-E66 Start with 9 Lives

Solomon no Kagi - Oujo Rihita no Namida (Japan) (Master System)

774-DE9-193 Infinite Time

Hang-On & Astro Warrior (USA) (Master System)

B64-169-3BE Hang-On - Infinite Time

Hang-On & Safari Hunt (USA) (Master System)

B60-EA9-3BE Hang-On - Infinite Time

Hang-On (Japan) (Master System)

B64-85D-3BE Infinite Time

Hang-On (Europe) (Master System)

B64-12D-3BE Infinite Time

Mick & Mack as the Global Gladiators (Europe) (Master System)

00D4EA:3C Freeze Timer
7E1-B8C-3B7 Infinite Health
B62-06E-3BE Infinite Lives
009-77B-3BE Infinite Time
020-33C-E6E Each M icon counts as 2
030-33C-E6E Each M icon counts as 3
040-33C-E6E Each M icon counts as 4
050-33C-E6E Each M icon counts as 5
060-33C-E6E Each M icon counts as 6
070-33C-E6E Each M icon counts as 7
080-33C-E6E Each M icon counts as 8
090-33C-E6E Each M icon counts as 9
00D512:86 Enable Cheats! Menu in Options (Disable once in Cheat Menu)
00D512:A6 Enable Infinite Shield Cheat
00D512:C6 Enable Infinite Lives Cheat
00D512:E6 Enable Infinite Lives and Infinite Shield Cheat
00D512:00 Disable Infinite Lives and Infinite Shield Cheat

Wimbledon II (Europe) (Master System)

3AE-FF7-2A2 Infinite Attribute Points (Tour Mode)
1E9-A37-B3A Start with 30 Attribute Points, instead of 20 (Tour Mode)
289-A37-B3A Start with 40 Attribute Points (Tour Mode)
329-A37-B3A Start with 50 Attribute Points (Tour Mode)
3C9-A37-B3A Start with 60 Attribute Points (Tour Mode)
469-A37-B3A Start with 70 Attribute Points (Tour Mode)
509-A37-B3A Start with 80 Attribute Points (Tour Mode)
00CB2F:50 Infinite Attribute Points (Tour Mode)
00C436:14 Max Speed (Tour Mode)
00C437:14 Max Power (Tour Mode)
00C438:14 Max Skill (Tour Mode)
00C439:14 Max Stamina (Tour Mode)
00CAD1:00 P1 Score is always 0
00CAD1:01 P1 Score is always 15
00CAD1:02 P1 Score is always 30
00CAD1:03 P1 Score is always 40 (Next Point by P1 Wins Game, unless P2 has 40)
00CAD1:04 P1 Score is always 40 Advantage (Next Point by P1 Wins Game)
00CAD0:00 P2 Score is always 0
00CAD0:01 P2 Score is always 15
00CAD0:02 P2 Score is always 30
00CAD0:03 P2 Score is always 40 (Next Point by P2 Wins Game, unless P1 has 40)
00CAD0:04 P2 Score is always 40 Advantage (Next Point by P2 Wins Game)
00CAD5:00 P1 Games Won is always 0
00CAD5:01 P1 Games Won is always 1
00CAD5:02 P1 Games Won is always 2
00CAD5:03 P1 Games Won is always 3
00CAD5:04 P1 Games Won is always 4
00CAD5:05 P1 Games Won is always 5 (Next Game Won by P1 Wins Set, unless P2 also has 5 or 6 Games Won)
00CAD5:06 P1 Games Won is always 6 (Next Game Won by P1 Wins Set)
00CAD2:00 P2 Games Won is always 0
00CAD2:01 P2 Games Won is always 1
00CAD2:02 P2 Games Won is always 2
00CAD2:03 P2 Games Won is always 3
00CAD2:04 P2 Games Won is always 4
00CAD2:05 P2 Games Won is always 5 (Next Game Won by P2 Wins Set, unless P1 also has 5 or 6 Games Won)
00CAD2:06 P2 Games Won is always 6 (Next Game Won by P2 Wins Set)

Halley Wars (USA, Europe) (Game Gear)

00C099:0A Infinite Credits
3A5-34F-2A2 Infinite Credits

Jurassic Park (Europe) (Master System)

189-79D-6EA Invincibility - Action Stages
3A5-C18-2A2 Infinite Health - Arcade Stages
7E9-AAD-3B7 Infinite Health - Action Stages
3A9-799-2A2 Infinite Lives
00A-C09-3BE Infinite Continues
004-B1A-3BE Infinite Medkit
00DD90:FF Invincibility (after being hit) - Action Stages
00CA00:03 Infinite Health - Arcade Stages
00C1EA:03 Infinite Health - Action Stages
00C030:63 Infinite Lives
00C034:63 Infinite Continues
00C033:09 Infinite Medkit

credit: Mezmorize for Invincibility - Action Stages

Tails Adventures (World) (En,Ja) (Game Gear)

00D3B0:FF Infinite Flight
00D02C:FF Enable Level Select on Map
00D030:FF Have all Items and Chaos Emeralds (1 of 3)
00D031:FF Have all Items and Chaos Emeralds (2 of 3)
00D032:FF Have all Items and Chaos Emeralds (3 of 3)

Klax (USA, Europe) (Game Gear)

3A1-44C-2A2 Infinite Credits

Klax (Europe) (Master System)

3A4-5EC-2A2 Infinite Drops
3A2-78C-2A2 Infinite Credits

Dynamite Duke (Europe) (Master System)

7E2-FBC-3B7 Infinite Health
009-C3C-3BE Infinite Lives
00E-C6B-3BE Infinite Credits
7E5-94B-3B7 Infinite Ammo
3AD-76C-2A2 Infinite Dynamite Punches

Dynamite Dux (Europe) (Master System)

00D73E:01 Invincibility (after being hit) (1 of 2)
00D73F:09 Invincibility (after being hit) (2 of 2)

Lemmings (Europe) (Master System)

00C-C4D-19E Infinite use of all types of lemmings
7E9-C5F-3B7 Infinite Time

Power Strike (USA, Europe) (Master System)

001-0F9-3BE Infinite Lives

Aleste (Japan) (Master System)

00E-E4A-3BE Infinite Lives

Rainbow Islands - Story of the Bubble Bobble 2 (Europe) (Master System)

053-9AE-E66 Start with 5 Lives, instead of 3
073-9AE-E66 Start with 7 Lives
093-9AE-E66 Start with 9 Lives

Line of Fire (Europe) (Master System)

00CB93:09 Infinite Continues
00CB94:09 Infinite Missiles (1 of 3)
00CB95:09 Infinite Missiles (2 of 3)
00CB96:09 Infinite Missiles (3 of 3)
002-4FC-3BE Invincibility (blinking) (Enable before start of level or after dying)
003-B0C-3BE Infinite Lives
001-489-3BE Infinite Continues
7E3-B3B-3B7 Infinite Missiles

Flash, The (Europe) (Master System)

3AB-3CD-2A2 Invincibility (after being hit)
3AE-BEC-2A2 Infinite Health
3AE-83F-2A2 Infinite Time

Zillion II - The Tri Formation (World) (Master System)

3A9-DEE-2A2 Infinite Health
B6E-90B-3BE Infinite Lives

Woody Pop - Shinjinrui no Block Kuzushi (Japan) (Master System)

B68-5FE-3BE Infinite Balls
056-98F-E66 Start with 5 Balls, instead of 3
096-98F-E66 Start with 9 Balls
0F6-98F-E66 Start with 15 Balls

Ghost House (USA, Europe) (Master System)

3A6-AFF-2A2 Infinite Health
003-5EF-3BE Infinite Lives

Ghost House (Japan) (Master System)

3A6-71F-2A2 Infinite Health
003-20F-3BE Infinite Lives

Golfamania (Europe) (Master System)

00C778:01 Always on 1st Stroke
7EF-E5D-3B7 Always on Same Stroke

Forgotten Worlds (Europe) (Master System)

3A3-4ED-2A2 Infinite Health
2A4-118-6E2 Infinite Zenny

Rambo - First Blood Part II (USA) (Master System)

00B-62F-3BE P1 Inifnite Lives
005-7EE-3BE P1 Infinite Arrow-Bombs
00B-A5F-3BE P2 Infinite Lives
008-31E-3BE P2 Infinite Arrow-Bombs
056-F3F-E66 Start with 5 Lives, instead of 3 - Both Players
076-F3F-E66 Start with 7 Lives - Both Players
096-F3F-E66 Start with 9 Lives - Both Players
07B-CFE-F7E P1 Start with 7 Arrow-Bombs, instead of 5
09B-CFE-F7E P1 Start with 9 Arrow-Bombs
07C-22E-F7E P2 Start with 7 Arrow-Bombs, instead of 5
09C-22E-F7E P2 Start with 9 Arrow-Bombs

Kenseiden (USA, Europe) (Master System)

3A2-18E-2A2 Invincibility (after being hit)
3A3-A5A-2A2 Infinite Health
3A7-EDE-2A2 Infinite Lives
030-34E-E62 Start with 3 Lives, instead of 2
050-34E-E62 Start with 5 Lives
070-34E-E62 Start with 7 Lives
090-34E-E62 Start with 9 Lives

Kenseiden (Japan) (Master System)

3A1-EBE-2A2 Invincibility (after being hit)
3A3-78A-2A2 Infinite Health
3A7-C0E-2A2 Infinite Lives
030-07E-E62 Start with 3 Lives, instead of 2
050-07E-E62 Start with 5 Lives
070-07E-E62 Start with 7 Lives
090-07E-E62 Start with 9 Lives

Road Rash (USA) (Game Gear)
Road Rash (Europe) (Game Gear)

7E3-064-3B7 Infinite Bike Health (Ignore Display) (1 of 2)
7E5-0F4-3B7 Infinite Bike Health (Ignore Display) (2 of 2)

Road Rash (Europe) (Master System)

7E3-064-3B7 Infinite Bike Health (Ignore Display) (1 of 2)
7E5-0F4-3B7 Infinite Bike Health (Ignore Display) (2 of 2)
3AD-D7E-2A2 Infinite Time
00B-39C-E62 Don't lose speed on grass
3EB-36C-08A Always travel at max speed (must press 1 button to start moving) (1 of 2)
FFB-37C-E62 Always travel at max speed (must press 1 button to start moving) (2 of 2)
3E8-BCC-916 Start with 2x bike health
FF8-BCC-916 Start with mega bike health

Credit Galoob for Don't lose speed on grass

Asterix (Europe) (En,Fr) (Master System)
Asterix (Europe) (En,Fr) (Rev 1) (Master System)

00D-90F-3BE Infinite Time

Mick & Mack as the Global Gladiators (USA, Europe) (Game Gear)

7E1-34C-3B7 Infinite Health
00D510:9C Enable Cheats! Menu in Options (Disable once in Cheat Menu)
00D510:BC Enable Infinite Shield Cheat
00D510: DC Enable Infinite Lives Cheat
00D510:FC Enable Infinite Lives and Infinite Shield Cheat
00D510:00 Disable Infinite Lives and Infinite Shield Cheat

Battle Out Run (Europe) (Master System)

3AF-17E-2A2 Infinite Time
3AF-4ED-2A2 Infinite Nitro
2AD-979-6E2 Infinite Money
00C19E:00 Freeze Timer
00C2E8:20 Infinite Nitro
00C2E5:FF Infinite Money (1 of 2)
00C2E6:FF Infinite Money (2 of 2)

Mega Man (USA) (Game Gear)

B61-13B-3BE Invincibility

Super Return of the Jedi (USA, Europe) (Game Gear)

0C2-2DE-E6E Heart pickups completely refill health
05E-EAC-E66 Start with 5 Lives, instead of 3
07E-EAC-E66 Start with 7 Lives
09E-EAC-E66 Start with 9 Lives
00D9EC:00 Character Modifier - Luke Skywalker
00D9EC:01 Character Modifier - Hans Solo
00D9EC:02 Character Modifier - Chewbacca
00D9EC:03 Character Modifier - Ewok
00D9EC:04 Character Modifier - Leia 1
00D9EC:05 Character Modifier - Leia 2

Defenders of Oasis (USA, Europe) (Game Gear)

6E9-C19-3BF Infinite HP - All Characters
2A0-609-6E2 Infinite MP - Genie

Magical Puzzle Popils (World) (En,Ja) (Game Gear)

B66-5CB-3BE Infinite Lives

Pop Breaker (Japan) (Game Gear)

3A3-40E-2A2 Infinite Lives
00C4A7:09 Infinite Lives

Wagyan Land (Japan) (Game Gear)

00C0C1:01 Invincibility

Side Pocket (USA) (Game Gear)

027-80E-E6E Balls pocketed are worth 200, instead of 100
037-80E-E6E Balls pocketed are worth 300
047-80E-E6E Balls pocketed are worth 400
057-80E-E6E Balls pocketed are worth 500
067-80E-E6E Balls pocketed are worth 600
077-80E-E6E Balls pocketed are worth 700
087-80E-E6E Balls pocketed are worth 800
097-80E-E6E Balls pocketed are worth 900

[terpsfan101]

Probably the last large batch of MS/GG codes:

Quartet (USA, Europe) (Master System)

00E-89A-3BE Invincibility (after being hit) - Both Players
B69-42D-3BE Infinite Health - Both Players (1 of 2)
7E9-22E-3B7 Infinite Health - Both Players (2 of 2)
002-ABD-3BE P1 Infinite Lives
002-ECD-3BE P2 Infinite Lives

Double Target - Cynthia no Nemuri (Japan) (Master System)

00E-7AA-3BE Invincibility (after being hit) - Both Players
B69-33D-3BE Infinite Health - Both Players (1 of 2)
7E9-22E-3B7 Infinite Health - Both Players (2 of 2)
002-ABD-3BE P1 Infinite Lives
002-ECD-3BE P2 Infinite Lives

Lucky Dime Caper Starring Donald Duck, The (Europe) (Master System)

00C08C:04 Freeze Timer
003-39F-3BE Infinite Time
040-D3E-E6E Start with 5 Health Units (don't pickup stars)
060-D3E-E6E Start with 7 Health Units (don't pickup stars)
080-D3E-E6E Start with 9 Health Units (don't pickup stars)
058-30F-E66 Start with 5 Lives, instead of 3
078-30F-E66 Start with 7 Lives
098-30F-E66 Start with 9 Lives

Golden Axe (USA, Europe) (Master System)

7E4-4CD-3B7 Infinite Health

Cheese Cat-astrophe Starring Speedy Gonzales (Europe) (En,Fr,De,Es) (Master System)

001-F3B-3BE Infinite Health

Cheese Cat-Astrophe Starring Speedy Gonzales (Europe) (En,Fr,De,Es) (Game Gear)

00F-097-3BE Infinite Lives

Battlemaniacs (Brazil) (Master System)

B61-689-3BE Infinite Health - Both Players
B61-6E9-3BE Infinite Lives - Both Players
3AB-4BC-2A2 Infinite Continues

Space Harrier (Japan, USA) (Master System)

3A5-9CD-2A2 Invincibility (after dying)
3A7-9DD-2A2 Infinite Lives

Space Harrier (Europe) (Master System)

3A5-EDD-2A2 Invincibility (after dying)
3A7-EED-2A2 Infinite Lives

Space Harrier 3-D (USA, Europe) (Master System)
Space Harrier 3D (Japan) (Master System)

C33-3DF-E61 Enable 2-D Mode (1 of 2)
C32-9FF-E61 Enable 2-D Mode (2 of 2)
B60-D69-3BE Infinite Lives

Out Run 3-D (Europe) (Master System)

3E1-31F-7F1 Enable 2-D Mode
85A-99E-E68 Start with 85 seconds, instead of 80
90A-99E-E68 Start with 90 seconds
95A-99E-E68 Start with 95 seconds
99A-99E-E68 Start with 99 seconds
65C-FFC-6EB Checkpoint adds 65 seconds, instead of 60
70C-FFC-6EB Checkpoint adds 70 seconds
75C-FFC-6EB Checkpoint adds 75 seconds
80C-FFC-6EB Checkpoint adds 80 seconds
85C-FFC-6EB Checkpoint adds 85 seconds
90C-FFC-6EB Checkpoint adds 90 seconds
95C-FFC-6EB Checkpoint adds 95 seconds
99C-FFC-6EB Checkpoint adds 99 seconds

Out Run (World) (Master System)

00DE02:3C Freeze Timer
00E-F9C-3BE Infinite Time

Astro Warrior (Japan, USA) (Master System)

3A9-0CF-2A2 Invincibility
3A1-5CF-2A2 Infinite Lives - 1P Game
3A1-9DF-2A2 P1 Infinite Lives - 2P Game
3A1-E6F-2A2 P2 Infinite Lives - 2P Game

Astro Warrior & Pit Pot (Europe) (Master System)
Hang-On & Astro Warrior (USA) (Master System)

3A9-20F-2A2 Astro Warrior - Invincibility
3A1-63F-2A2 Astro Warrior - Infinite Lives - 1P Game
3A1-A4F-2A2 Astro Warrior - P1 Infinite Lives - 2P Game
3A1-EDF-2A2 Astro Warrior - P2 Infinite Lives - 2P Game

SpellCaster (USA, Europe) (Master System)

5BD-7CD-A27 Infinite MP

Desert Strike (Europe) (En,Fr,De,Es) (Master System)

034-2AE-E62 Start with and have a capacity of 856 armor, instead of 600 (after 1st life)
E74-29E-80B Start with and have a capacity of 999 armor (after 1st life) (1 of 2)
034-2AE-E62 Start with and have a capacity of 999 armor (after 1st life) (2 of 2)

Fantasy Zone II - The Tears of Opa-Opa (USA, Europe) (Master System)

004-08E-A28 Infinite Health (Power) (1 of 2)
004-0FE-D56 Infinite Health (Power) (2 of 2)
006-6EB-3BE Infinite Lives
B64-40E-3BE Infinite Weapon Time
1A3-BFA-A22 Infinite Money (1 of 3)
1A3-C5A-A22 Infinite Money (2 of 3)
1A3-CBA-A22 Infinite Money (3 of 3)
10D-42E-C4A Start a new game with 2x Health (Power)
18D-42E-C4A Start a new game with 3x Health (Power)
20D-42E-C4A Start a new game with 4x Health (Power)
28D-42E-C4A Start a new game with 5x Health (Power)
30D-42E-C4A Start a new game with Max Health (Power)

Fantasy Zone (World) (Rev 2) (Master System)
Fantasy Zone (World) (Rev 1) (Beta) (Master System)

00C063:xx Round Modifier (xx=00-07) (1 of 2)
00C064:xx Round Modifier (xx=00-07) (2 of 2)
B65-DBD-3BE Infinite Lives
000-26E-3BE Infinite Weapon Time
0A5-79F-E62 Infinite Money (1 of 3)
0A5-7FF-E62 Infinite Money (2 of 3)
0A5-85F-E62 Infinite Money (3 of 3)

Wonder Boy III - The Dragon's Trap (USA, Europe) (Master System)

00A-63B-F7E Invincibility
094-97F-E6A Start a new game with 999,999 Gold

Credit: mezmorize

Wonder Boy - The Dragon's Trap (Europe) (Game Gear)

7E6-72A-3B7 Infinite Items

Marble Madness (Europe) (Master System)

00DFC4:B3 Infinite Time (enable after timer screen)
3AD-16F-2A2 Infinite Time

Renegade (Europe) (Master System)

00C3AB:99 Infinite Lives - Both Players
00C3A2:00 Freeze Timer
3A2-02A-2A2 Infinite Health - Both Players
3A4-1CA-2A2 Infinite Lives - Both Players
3A3-E8F-2A2 Infinite Time

Hang-On & Safari Hunt (USA) (Master System)

00E-E1F-3BE Safari Hunt - Infinite Bullets

Alien Storm (Europe) (Master System)

00C103:01 Enable Cheat Mode (On Controller 2, Press 1 or 2 to Skip Stages and Up to Restore Health and Weapons Energy)

Zaxxon 3-D (World) (Master System)

7E4-D1D-3B7 Invincibility
3A1-5BB-2A2 Infinite Lives
2A7-C5D-6E2 Infinite Fuel

Cool Spot (Europe) (Master System)

00D08F:3C Freeze Timer
C9F-4AD-E69 Invincibility
7E5-43C-3B7 Infinite Health
B64-80E-3BE Infinite Lives
00D-69B-3BE Infinite Time

Gear Works (USA) (Game Gear)

00DCAD:00 Low Engine Temperature
3A5-ECF-2A2 Engine Temperature doesn't Increase
3AF-0AD-2A2 Infinite Lives
3AD-EEE-2A2 Infinite Targets
3AC-26E-2A2 Infinite Bombs
3AC-F7E-2A2 Infinite Oil

Fire & Forget II (Europe) (Master System)

3A2-CFF-2A2 Infinite Fuel
3A2-FBF-2A2 Infinite Flying
3A4-6AF-2A2 Infinite Lives
007-84F-3BE Infinite Rockets

Taito Chase H.Q. (Europe) (Master System)

00C237:00 Freeze Timer
00C222:03 Infinite Continues
2A4-F3D-6E2 Infinite Time
006-7AD-3BE Infinite Turbos
006-C6C-3BE Infinite Continues

Taito Chase H.Q. (USA) (Game Gear)

00C23D:00 Freeze Timer
00C289:03 Infinite Turbos
00C228:03 Infinite Continues
2A5-18D-6E2 Infinite Time
006-B4D-3BE Infinite Turbos
007-50C-3BE Infinite Continues

Taito Chase H.Q. (Japan) (Game Gear)

00C23D:00 Freeze Timer
00C289:03 Infinite Turbos
00C228:03 Infinite Continues
2A5-1ED-6E2 Infinite Time
006-BAD-3BE Infinite Turbos
007-56C-3BE Infinite Continues

GP Rider (Europe) (Master System)

00CA2D:99 Infinite Time
00CA2E:00 Freeze Timer
3A9-88F-2A2 Infinite Time

Land of Illusion Starring Mickey Mouse (Europe) (Master System)

18C-E77-6EA Invincibility
03D-FFD-E62 Start a new game with 3 health stars
04D-FFD-E62 Start a new game with 4 health stars
05D-FFD-E62 Start a new game with 5 health stars

Royal Stone - Hirakareshi Toki no Tobira (Japan) (Game Gear)
Royal Stone - Hirakareshi Toki no Tobira (Japan) [T-En by Aeon Genesis v1.00] (Game Gear)

00D66D:E7 Infinite HP - In-Battle - All Characters (1 of 2)
00D66E:03 Infinite HP - In-Battle - All Characters (2 of 2)
3A0-919-2A2 Infinite HP - In-Battle - All Characters (1 of 2)
3A0-959-2A2 Infinite HP - In-Battle - All Characters (2 of 2)

Shining Force Gaiden - Final Conflict (Japan) (Game Gear)
Shining Force Gaiden - Final Conflict (Japan) [T-En by Shining Force Central v20060707] (Game Gear)

CD9-D8B-5DD Infinite HP - all characters (1 of 12)
D09-D9B-E63 Infinite HP - all characters (2 of 12)
009-DAB-4C5 Infinite HP - all characters (3 of 12)
7A0-D0F-E6A Infinite HP - all characters (4 of 12)
FE0-D1F-E6A Infinite HP - all characters (5 of 12)
800-D2F-E6A Infinite HP - all characters (6 of 12)
280-D3F-E6A Infinite HP - all characters (7 of 12)
020-D4F-E6A Infinite HP - all characters (8 of 12)
ED0-D5F-E6A Infinite HP - all characters (9 of 12)
420-D6F-E6A Infinite HP - all characters (10 of 12)
EB0-D7F-E6A Infinite HP - all characters (11 of 12)
C90-D8F-E6A Infinite HP - all characters (12 of 12)

credit nolberto82

Rescue Mission (USA, Europe) (Master System)

B66-3BE-3BE Infinite Lives

R-Type (World) (Master System)

05F-EBF-E66 Start with 5 Lives, instead of 3
09F-EBF-E66 Start with 9 Lives
19F-EBF-E66 Start with 25 Lives
32F-EBF-E66 Start with 50 Lives
4BF-EBF-E66 Start with 75 Lives
63F-EBF-E66 Start with 99 Lives
05F-DEF-E62 Start with 5 Continues, instead of 2
09F-DEF-E62 Start with 9 Continues
25F-DEF-E62 Start with 25 Continues
50F-DEF-E62 Start with 50 Continues
75F-DEF-E62 Start with 75 Continues
99F-DEF-E62 Start with 99 Continues

Ninja Gaiden (Europe) (Master System)

C9F-14D-E69 Invincibility
00DFC4:FF Enable Invincibility Cheat
00DFC3:FF Enable Infinite Weapons Cheat
00DFC4:00 Disable Invincibility Cheat
00DFC3:00 Disable Infinite Weapons Cheat

Shinobi (USA, Europe) (Master System)
Shinobi (Japan) (Master System)

063-31F-E6A Stage Select after Title Screen
0C5-F0F-F72 Start with 2x Health
125-F0F-F72 Start with 3x Health
035-D7F-E62 Start with 3 Lives, instead of 2
045-D7F-E62 Start with 4 Lives

Out Run (Europe) (Game Gear)

00C168:00 Freeze Timer
003-79E-3BA Infinite Time
084-BFC-F76 Start with 80 seconds, instead of 70
094-BFC-F76 Start with 90 seconds
094-BFC-F76 Start with 99 seconds (1 of 2)
094-BEC-E6A Start with 99 seconds (2 of 2)
07A-4F7-F72 Checkpoint adds 70 seconds, instead of 60
08A-4F7-F72 Checkpoint adds 80 seconds
09A-4F7-F72 Checkpoint adds 90 seconds

Out Run (Japan) (Game Gear)

00C168:00 Freeze Timer
002-2CE-3BA Infinite Time
083-36C-F76 Start with 80 seconds, instead of 70
093-36C-F76 Start with 90 seconds
093-36C-F76 Start with 99 seconds (1 of 2)
093-35C-E6A Start with 99 seconds (2 of 2)
07A-337-F72 Checkpoint adds 70 seconds, instead of 60
08A-337-F72 Checkpoint adds 80 seconds
09A-337-F72 Checkpoint adds 90 seconds

Penguin Adventure (Korea) (Unl) (Pirate) (Master System)

00C090:09 Infinite Lives
00C08B:99 Infinite Time (1 of 2)
00C08C:09 Infinite Time (2 of 2)

Defenders of Oasis (USA, Europe) (Game Gear)

002-A45-3BE Infinite Items

Item Slot Codes:

00DB7E:xx Item Slot 01
00DB80:xx Item Slot 02
00DB82:xx Item Slot 03
00DB84:xx Item Slot 04
00DB86:xx Item Slot 05
00DB88:xx Item Slot 06
00DB8A:xx Item Slot 07
00DB8C:xx Item Slot 08
00DB8E:xx Item Slot 09
00DB90:xx Item Slot 10
00DB92:xx Item Slot 11
00DB94:xx Item Slot 12
00DB96:xx Item Slot 13
00DB98:xx Item Slot 14
00DB9A:xx Item Slot 15
00DB9C:xx Item Slot 16
00DB9E:xx Item Slot 17
00DBA0:xx Item Slot 18
00DBA2:xx Item Slot 19
00DBA4:xx Item Slot 20
00DBA6:xx Item Slot 21
00DBA8:xx Item Slot 22
00DBAA:xx Item Slot 23
00DBAC:xx Item Slot 24
00DBAE:xx Item Slot 25
00DBB0:xx Item Slot 26
00DBB2:xx Item Slot 27
00DBB4:xx Item Slot 28
00DBB6:xx Item Slot 29
00DBB8:xx Item Slot 30
00DBBA:xx Item Slot 31
00DBBC:xx Item Slot 32
00DBBE:xx Item Slot 33
00DBC0:xx Item Slot 34
00DBC2:xx Item Slot 35
00DBC4:xx Item Slot 36
00DBC6:xx Item Slot 37
00DBC8:xx Item Slot 38
00DBCA:xx Item Slot 39
00DBCC:xx Item Slot 40
00DBCE:xx Item Slot 41
00DBD0:xx Item Slot 42
00DBD2:xx Item Slot 43
00DBD4:xx Item Slot 44
00DBD6:xx Item Slot 45
00DBD8:xx Item Slot 46
00DBDA:xx Item Slot 47
00DBDC:xx Item Slot 48
00DBDE:xx Item Slot 49
00DBE0:xx Item Slot 50
00DBE2:xx Item Slot 51
00DBE4:xx Item Slot 52
00DBE6:xx Item Slot 53
00DBE8:xx Item Slot 54
00DBEA:xx Item Slot 55
00DBEC:xx Item Slot 56
00DBEE:xx Item Slot 57
00DBF0:xx Item Slot 58
00DBF2:xx Item Slot 59
00DBF4:xx Item Slot 60
00DBF6:xx Item Slot 61
00DBF8:xx Item Slot 62
00DBFA:xx Item Slot 63
00DBFC:xx Item Slot 64

Item Modifiers:

01 Ring one
02 Ring two
03 Ring ash
04 Lamp
05 Passport
06 Key of S
07 Mirror
08 Key of G
09 Hammer
0A Key of T
0B Dead Eye
0C Evil Eye
0D Amulet
0E Shamshir
0F Kutar
10 Saber
11 Jambiya
12 Falchion
13 Chakram
14 Kris
15 Talwar
16 Kwarnaf
17 Hilt
18 Firenar
19 Holynar
1A Poisonar
1B Mantle
1C Cape
1D Cloak
1E Shield
1F Cuirass
20 Herberk
21 Sp. Mantle
22 Sp. Cape
23 Sp. Cloak
24 Bandana
25 Turban
26 Circlet
27 Mask
28 Helm
29 Crown
2A Pillow
2B Hemp
2C Silk
2D Plating
2E Gilding
2F Power Pot
30 Speed Pot
31 Life Pot
32 Herb
33 Holy Herb
34 Snake Act
35 Worm Act
36 Barrel
37 Tailsman
38 F. Stone
39 H. Stone
3A Bottle
3B Barbado
3C Key of E
3D Crystal

[terpsfan101]

Here's some more MS/GG codes, with a few SG-1000 codes at the end:

Lunar - Sanposuru Gakuen (Japan) (Game Gear)
Lunar - Walking School (Japan) [T-En by Aeon Genesis v1.00] [n] (Game Gear)

6E5-54A-3BF Infinite HP - All Characters (1 of 2)
665-57A-3BB Infinite HP - All Characters (2 of 2)
6ED-F6F-3BF Infinite MP - All Characters (1 of 2)
66D-F9F-3BB Infinite MP - All Characters (2 of 2)
003-E6C-3B2 Infinite Items

Bare Knuckle ~ Streets of Rage (World) (Game Gear)

00CD0A:09 Infinite Continues
00CEF0:4B Freeze Timer
B62-E77-3BE Infinite Continues
057-44F-E66 Start with 5 Continues, instead of 3
077-44F-E66 Start with 7 Continues
097-44F-E66 Start with 9 Continues

Bare Knuckle II ~ Streets of Rage 2 ~ Streets of Rage II (World) (Game Gear)

00C9A7:09 Infinite Continues
00C73B:35 Freeze Timer
B6F-837-3BE Infinite Continues
0EE-E19-F76 Apple replenishes 2x as much health
17E-E19-F76 Apple completely replenishes health
0FE-B1D-912 Special Attack Charges 2x Faster
23E-F79-B36 Start with 1.5x Health (1 of 2)
234-A5B-B36 Start with 1.5x Health (2 of 2)
2EE-F79-B36 Start with 2x Health (1 of 2)
2E4-A5B-B36 Start with 2x Health (2 of 2)
3AE-F79-B36 Start with 2.5x Health (1 of 2)
3A4-A5B-B36 Start with 2.5x Health (2 of 2)
45E-F79-B36 Start with 3x Health (1 of 2)
454-A5B-B36 Start with 3x Health (2 of 2)
053-24D-E66 Start with 5 Continues, instead of 3
073-24D-E66 Start with 7 Continues
093-24D-E66 Start with 9 Continues

Star Wars (USA) (Game Gear)
Star Wars (Europe) (Game Gear)

C9C-ADC-E69 Invincibility (after being hit)

Star Wars (Europe) (Master System)

00D-C8B-19E Invincibility - Vehicle (after being hit) (disable to exit level)

Lion King, The (Europe) (Master System)

3A6-2F9-2A2 Infinite Health
3A6-8EC-2A2 Infinite Lives

Road Rash (Europe) (Master System)

B14-798-2A8 Almost Infinite Money
008-FF9-A24 Don't get Charged for Repairs and Fines
056-DBF-E6E Start with $5000, instead of $1000 - Both Players
096-DBF-E6E Start with $9000 - Both Players
256-DBF-E6E Start with $25000 - Both Players
506-DBF-E6E Start with $50000 - Both Players
756-DBF-E6E Start with $75000 - Both Players
996-DBF-E6E Start with $99000 - Both Players

00CED8:3F Infinite Health
00CEF8:1F Infinite Bike Health
00DF0B:09 P1 Infinite Money (1 of 3)
00DF0C:99 P1 Infinite Money (2 of 3)
00DF0D:99 P1 Infinite Money (3 of 3)
00DF2B:09 P2 Infinite Money (1 of 3)
00DF2C:99 P2 Infinite Money (2 of 3)
00DF2D:99 P2 Infinite Money (3 of 3)
00DF13:00 P1 Level Modifier - Level 1
00DF13:01 P1 Level Modifier - Level 2
00DF13:02 P1 Level Modifier - Level 3
00DF13:03 P1 Level Modifier - Level 4
00DF13:04 P1 Level Modifier - Level 5
00DF33:00 P2 Level Modifier - Level 1
00DF33:01 P2 Level Modifier - Level 2
00DF33:02 P2 Level Modifier - Level 3
00DF33:03 P2 Level Modifier - Level 4
00DF33:04 P2 Level Modifier - Level 5
00DF14:00 P1 Bike Modifier - Shuriken 400
00DF14:01 P1 Bike Modifier - Panda 600
00DF14:02 P1 Bike Modifier - Banzai 750
00DF14:03 P1 Bike Modifier - Kamikaze 750
00DF14:04 P1 Bike Modifier - Shuriken 1000
00DF14:05 P1 Bike Modifier - Ferruci 850
00DF14:06 P1 Bike Modifier - Panda 750
00DF14:07 P1 Bike Modifier - Diablo 1000
00DF34:00 P2 Bike Modifier - Shuriken 400
00DF34:01 P2 Bike Modifier - Panda 600
00DF34:02 P2 Bike Modifier - Banzai 750
00DF34:03 P2 Bike Modifier - Kamikaze 750
00DF34:04 P2 Bike Modifier - Shuriken 1000
00DF34:05 P2 Bike Modifier - Ferruci 850
00DF34:06 P2 Bike Modifier - Panda 750
00DF34:07 P2 Bike Modifier - Diablo 1000

Road Rash (USA) (Game Gear)
Road Rash (Europe) (Game Gear)

B14-4D8-2A8 Almost Infinite Money
008-DD9-A24 Don't get Charged for Repairs and Fines
056-CDF-E6E Start with $5000, instead of $1000 - Both Players
096-CDF-E6E Start with $9000 - Both Players
256-CDF-E6E Start with $25000 - Both Players
506-CDF-E6E Start with $50000 - Both Players
756-CDF-E6E Start with $75000 - Both Players
996-CDF-E6E Start with $99000 - Both Players

00CED8:3F Infinite Health
00CEF8:1F Infinite Bike Health
00DF0B:09 P1 Infinite Money (1 of 3)
00DF0C:99 P1 Infinite Money (2 of 3)
00DF0D:99 P1 Infinite Money (3 of 3)
00DF2B:09 P2 Infinite Money (1 of 3)
00DF2C:99 P2 Infinite Money (2 of 3)
00DF2D:99 P2 Infinite Money (3 of 3)
00DF13:00 P1 Level Modifier - Level 1
00DF13:01 P1 Level Modifier - Level 2
00DF13:02 P1 Level Modifier - Level 3
00DF13:03 P1 Level Modifier - Level 4
00DF13:04 P1 Level Modifier - Level 5
00DF33:00 P2 Level Modifier - Level 1
00DF33:01 P2 Level Modifier - Level 2
00DF33:02 P2 Level Modifier - Level 3
00DF33:03 P2 Level Modifier - Level 4
00DF33:04 P2 Level Modifier - Level 5
00DF14:00 P1 Bike Modifier - Shuriken 400
00DF14:01 P1 Bike Modifier - Panda 600
00DF14:02 P1 Bike Modifier - Banzai 750
00DF14:03 P1 Bike Modifier - Kamikaze 750
00DF14:04 P1 Bike Modifier - Shuriken 1000
00DF14:05 P1 Bike Modifier - Ferruci 850
00DF14:06 P1 Bike Modifier - Panda 750
00DF14:07 P1 Bike Modifier - Diablo 1000
00DF34:00 P2 Bike Modifier - Shuriken 400
00DF34:01 P2 Bike Modifier - Panda 600
00DF34:02 P2 Bike Modifier - Banzai 750
00DF34:03 P2 Bike Modifier - Kamikaze 750
00DF34:04 P2 Bike Modifier - Shuriken 1000
00DF34:05 P2 Bike Modifier - Ferruci 850
00DF34:06 P2 Bike Modifier - Panda 750
00DF34:07 P2 Bike Modifier - Diablo 1000

Girl's Garden (Japan) (SG-1000)

3A5-E0D-2A2 Infinite Lives
3A8-42F-2A2 Infinite Honey
3A8-8ED-2A2 Infinite Time
04B-38D-E62 Start with 4 Lives, instead of 2
06B-38D-E62 Start with 6 Lives
07B-33D-F7E Start with 7 Honey
09B-33D-F7E Start with 9 Honey
00C00F:06 Infinite Lives
00C00E:09 Infinite Honey
00C019:01 Infinite Time
00C01A:09 Freeze Timer

Golgo 13 (Japan) (SG-1000)

00C231:3C Freeze Timer
3A7-A9E-2A2 Infinite Lives
B67-1EE-3BE Infinite Time

Gulkave (Japan) (SG-1000)

3A4-25D-2A2 Infinite Shield
002-5DA-3BE Infinite Lives
00C2AD:20 Infinite Shield
00C2C5:04 Infinite Lives

[terpsfan101]

Another glut of GG/MS codes:

Wonder Boy in Monster Land (USA, Europe) (Master System)

7E8-95C-3B7 Infinite Health
2AA-03C-6E2 Infinite Time
3A8-DAC-2A2 Infinite Revival Potion
1AA-78F-A22 Infinite Gold (1 of 2)
1AA-7EF-A22 Infinite Gold (2 of 2)
00A-B0B-3BE Infinite Magic Weapons

Golden Axe (USA, Europe) (Master System)

000-ABC-3B2 Infinite Magic

Zillion (USA) (Rev 1) (Master System)

00C112:04 Infinite Continues
B65-23D-3BE Infinite Continues

Zillion (Japan, Europe) (En,Ja) (Master System)

00C112:04 Infinite Continues
B64-DAD-3BE Infinite Continues

Bonanza Bros. (Europe) (Master System)

00C584:3C Freeze Timer
00C41E:FF Enable Stage Select in Options Menu
3A6-D5D-2A2 Invincibility (blinking) (after dying)
B65-E8D-3BE Infinite Lives
00B-26B-3BE Infinite Continues
B6A-53B-3BE Infinite Time

Time Soldiers (USA, Europe) (Master System)

004-72B-B32 Invincibility (blinking) (Enable before start of level or after dying) - Both Players
3A3-4E9-2A2 P1 Infinite Lives
3AA-1AA-2A2 P1 Infinite Special Weapons
3A4-049-2A2 P2 Infinite Lives
3AA-88A-2A2 P2 Infinite Special Weapons

Operation Wolf (Europe) (Master System)

3A1-B6D-2A2 Infinite Health (1 of 3)
3A7-71A-2A2 Infinite Health (2 of 3)
3A3-57D-2A2 Infinite Health (3 of 3)
3A4-C6E-2A2 Infinite Bullets (1 of 2)
3A4-D3E-2A2 Infinite Bullets (2 of 2)
3A5-14E-2A2 Infinite Grenades

Master of Darkness (Europe) (Master System)

C96-D1B-E69 Invincibility

credit mezmorize

Space Invaders (Japan) (SG-1000)

3A6-B7E-2A2 Infinite Lives - Both Players

Ninja Princess (Japan) (SG-1000)
Ninja Princess (Japan) [T-En by Goldenband v1.0] (SG-1000)

006-E2E-3BE Infinite Lives - Both Players
00C-F5E-4C6 Infinite Time

Hang-On II (Japan) (SG-1000)

00C04B:3C Freeze Timer
C9F-F1D-E69 Infinite Time

Monaco GP (Japan) (SG-1000)
Monaco GP (Japan) (Rev 1) (SG-1000)
Monaco GP (Japan) (Rev 2) (SG-1000)

00C201:04 Infinite Cars (Lives)

Wonder Boy III - The Dragon's Trap (USA, Europe) (Master System)

3AB-B9B-2A2 Infinite Revival (Blue) Potions
1AB-EFF-A22 Infinite Gold
3AC-89B-2A2 Infinite Keys

Wonder Boy - The Dragon's Trap (Europe) (Game Gear)

3AA-00B-2A2 Infinite Revival (Blue) Potions
1AD-53F-A22 Infinite Gold
3AA-D0B-2A2 Infinite Keys

Shinobi (USA, Europe) (Game Gear)
GG Shinobi, The (Japan) (Game Gear)

00D-50D-3BE Infinite Ninjitsu Magic

Out Run Europa (Europe) (Master System)

00C15C:13 Freeze Timer
3A7-87D-2A2 Infinite Time
7EC-C7E-3B7 Infinite Shields (1 of 2)
7EE-93E-3B7 Inifnite Shields (2 of 2)
3AC-8FF-2A2 Infinite Turbos
3A7-E5E-2A2 Infinite Ammo

Out Run Europa (Europe) (Game Gear)
Out Run Europa (USA) (Game Gear)

00C160:13 Freeze Timer
7EC-C7E-3B7 Infinite Shields (1 of 2)
7EE-93E-3B7 Inifnite Shields (2 of 2)

Land of Illusion Starring Mickey Mouse (Europe) (Master System)

001-A1E-3BE Infinite Air

Land of Illusion Starring Mickey Mouse (USA, Europe) (Game Gear)

001-33E-3BE Infinite Air
03F-22D-E62 Start a new game with 3 health units
04F-22D-E62 Start a new game with 4 health units
05F-22D-E62 Start a new game with 5 health units

Mortal Kombat (Europe) (Master System)

005-F88-91D P1 Invincibility (Projectiles stop you when they touch you. Walk forward or crouch to continue) (1 of 5)
005-F98-193 P1 Invincibility (Projectiles stop you when they touch you. Walk forward or crouch to continue) (2 of 5)
7B5-FA8-80E P1 Invincibility (Projectiles stop you when they touch you. Walk forward or crouch to continue) (3 of 5)
FE5-FB8-5D0 P1 Invincibility (Projectiles stop you when they touch you. Walk forward or crouch to continue) (4 of 5)
895-FC8-7F0 P1 Invincibility (Projectiles stop you when they touch you. Walk forward or crouch to continue) (5 of 5)
003-0AB-F79 P1 Infinite health
003-12B-F79 P2 Infinite health
00B-01C-3BE Infinite time
004-2B6-19E Infinite credits
DEB-876-5D3 Blood enabled
240-B9D-C4B P1 starts with 1/2 health
240-BFD-C4B P2 usually starts with 1/2 health
08B-BFA-F76 Start with 7 credits, instead of 6
09B-BFA-F76 Start with 8 credits
0AB-BFA-F76 Start with 9 credits

credit:

nolberto82 for Invincibility
Galoob for all codes except Invincibility

Dynamite Headdy (Brazil) (Master System)

7EF-83D-3B7 Infinite Health

Baku Baku Animal (Brazil) (Master System)

00C492:00 Freeze Timer
000-ABB-3BA Infinite Time

Alien 3 (USA, Europe) (Game Gear)

00C00A:67 Enable Level Select Menu (Press 2 while on Title Screen)

Alien 3 (Japan) (Game Gear)

00C00A:5C Enable Level Select Menu (Press 2 while on Title Screen)

Alien 3 (Europe) (Master System)

00C00A:C5 Enable Level Select Menu (Press 2 while on Title Screen)

NBA Jam - Tournament Edition (World) (Game Gear)

013-299-E6A Quick Hands Powerup - All Players
023-299-E6A Max Power Powerup - All Players
043-299-E6A Goaltending Powerup - All Players
083-299-E6A Offense Powerup - All Players
103-299-E6A Super Dunk Powerup - All Players
203-299-E6A On-Fire Powerup - All Players
403-299-E6A 3-Point Powerup - All Players
803-299-E6A Power Push Powerup - All Players
013-2A9-E6A Infinite Turbo Powerup - All Players
023-2A9-E6A Knockdown Both Opponents Powerup - All Players
043-2A9-E6A Super Speed Powerup - All Players
103-2A9-E6A Teleport Pass Powerup - All Players
403-2A9-E6A High Shots Powerup - All Players
FF3-299-E6A All Powerups - All Players (1 of 2)
573-2A9-E6A All Powerups - All Players (2 of 2)
4F3-299-E6A Powered-up Player (All Powerups except Power Push, Super Dunk, On-Fire, and Knockdown Both Opponents) - All Players (1 of 2)
553-2A9-E6A Powered-up Player (All Powerups except Power Push, Super Dunk, On-Fire, and Knockdown Both Opponents) - All Players (2 of 2)
033-299-E6A Better Defense Powerup (Quick Hands and Max Power) - All Players

[terpsfan101]

Running out of good SMS/GG games to find codes for:

Sonic The Hedgehog (USA, Europe) (Master System)

7EA-18C-3B7 Infinite Time
05C-4FE-E66 Start with 5 Lives, instead of 3 (Enable before Title Screen Loads)
09C-4FE-E66 Start with 9 Lives (Enable before Title Screen Loads)
19C-4FE-E66 Start with 25 Lives (Enable before Title Screen Loads)
32C-4FE-E66 Start with 50 Lives (Enable before Title Screen Loads)
4BC-4FE-E66 Start with 75 Lives (Enable before Title Screen Loads)
63C-4FE-E66 Start with 99 Lives (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Green Hill Zone, Act 2 (1 of 2) (Enable before Title Screen Loads)
01C-59E-91A Start on Green Hill Zone, Act 2 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Green Hill Zone, Act 3 (1 of 2) (Enable before Title Screen Loads)
02C-59E-91A Start on Green Hill Zone, Act 3 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Bridge Zone, Act 1 (1 of 2) (Enable before Title Screen Loads)
03C-59E-91A Start on Bridge Zone, Act 1 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Bridge Zone, Act 2 (1 of 2) (Enable before Title Screen Loads)
04C-59E-91A Start on Bridge Zone, Act 2 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Bridge Zone, Act 3 (1 of 2) (Enable before Title Screen Loads)
05C-59E-91A Start on Bridge Zone, Act 3 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Jungle Zone, Act 1 (1 of 2) (Enable before Title Screen Loads)
06C-59E-91A Start on Jungle Zone, Act 1 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Jungle Zone, Act 2 (1 of 2) (Enable before Title Screen Loads)
07C-59E-91A Start on Jungle Zone, Act 2 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Jungle Zone, Act 3 (1 of 2) (Enable before Title Screen Loads)
08C-59E-91A Start on Jungle Zone, Act 3 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Labyrinth Zone Act 1 (1 of 2) (Enable before Title Screen Loads)
09C-59E-91A Start on Labyrinth Zone Act 1 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Labyrinth Zone Act 2 (1 of 2) (Enable before Title Screen Loads)
0AC-59E-91A Start on Labyrinth Zone Act 2 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Labyrinth Zone Act 3 (1 of 2) (Enable before Title Screen Loads)
0BC-59E-91A Start on Labyrinth Zone Act 3 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Scrap Brain Zone, Act 1 (1 of 2) (Enable before Title Screen Loads)
0CC-59E-91A Start on Scrap Brain Zone, Act 1 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Scrap Brain Zone, Act 2 (1 of 2) (Enable before Title Screen Loads)
0DC-59E-91A Start on Scrap Brain Zone, Act 2 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Scrap Brain Zone, Act 3 (1 of 2) (Enable before Title Screen Loads)
0EC-59E-91A Start on Scrap Brain Zone, Act 3 (2 of 2) (Enable before Title Screen Loads)
00C-5DE-5D4 Start on Sky Base Zone, Act 1 (1 of 2) (Enable before Title Screen Loads)
0FC-59E-91A Start on Sky Base Zone, Act 1 (2 of 2) (Enable before Title Screen Loads)

credit Galoob for Start on Zone/Act codes

X-Men - Mojo World (Brazil) (Master System)

3A9-087-2A2 Infinite Health

Sonic Drift 2 (Japan, USA) (Game Gear)

0E8-22C-C42 Infinite Item Use

Ms. Pac-Man (USA) (Game Gear)

00C395:00 Infinite Power Pill Time
3AC-F39-2A2 Infinite Lives - 1P Game
3AD-219-2A2 P1 Infinite Lives - 2P Game
3AD-359-2A2 P2 Infinite Lives - 2P Game
3A2-3BA-2A2 Infinite Power Pill Time
054-DF9-E66 P1 Start with 5 lives
084-DF9-E66 P1 Start with 8 lives
0A4-DF9-E66 P1 Start with 10 lives
054-E99-E66 P2 Start with 5 lives
084-E99-E66 P2 Start with 8 lives
0A4-E99-E66 P2 Start with 10 lives

Ms. Pac-Man (Europe) (Master System)

00DA4E:05 P1 Infinite Lives (P2 also in alternating game)
00DA93:05 P2 Infinite Lives (except Alternating Game)
00D768:82 Infinite Power Pill Time
00A-75D-3BE Infinite Lives - Both Players (except Alternating Game)
6E4-E3B-3BF Infinite Lives - Both Players (Alternating Game)
3AF-44E-2A2 Infinite Power Pill Time
04B-02D-E66 Start with 4 Lives, instead of 3 - Both Players
05B-02D-E66 Start with 5 Lives - Both Players

Pac-Man (USA) (Game Gear)

00C17F:AF Infinite Power Pill Time

Pac-Man (Japan) (En) (Game Gear)

00C17F:AF Infinite Power Pill Time
3A8-966-2A2 Infinite Lives
055-546-E66 Start with 5 lives
085-546-E66 Start with 8 lives
0A5-546-E66 Start with 10 lives

Golden Axe (USA, Europe) (Master System)

00C015:00 Infinite Continues
007-DDE-3BA Infinite Continues

Gunstar Heroes (Japan) (Game Gear)

96C-595-7FB Start with 1.5x Health
C8C-595-7FB Start with 2x Health
FFC-595-7FB Start with 2.5x Health

Bubble Bobble (Europe) (Master System)
Final Bubble Bobble (Japan) (Master System)

00DC8B:C7 Select 1P/2P Continue for Round Select (Press Up or Down to change Rounds)
001-955-A22 Hit Anywhere - Normal Enemies (1 of 4)
001-9E5-C4E Hit Anywhere - Normal Enemies (2 of 4)
186-D36-191 Hit Anywhere - Normal Enemies (3 of 4)
1A6-D46-806 Hit Anywhere - Normal Enemies (4 of 4)
00E-F5E-5D4 Start with letters X and T

credit:

nolberto82 for Hit Anywhere
Galoob for Start with letters X and T

Bubble Bobble (USA, Europe) (Game Gear)

00DC8B:C7 Select 1P Continue for Round Select (Press Up or Down to change Rounds)

Enduro Racer (USA, Europe) (Master System)

B6B-59E-3BE Infinite Time
7E4-0DE-3B7 Take No Damage
2A1-88A-6E2 Infinite Points
003-BDB-F7A Enable Track Select on Title Screen

Enduro Racer (Japan) (Master System)

B6D-D7E-3BE Infinite Time
7E6-59E-3B7 Take No Damage
2A0-289-6E2 Infinite Points
006-54B-F7A Enable Track Select on Title Screen

[terpsfan101]

Mighty Morphin Power Rangers - The Movie (USA) (Genesis)

FF603C:01FF P1 Infinite Health
FF613C:01FF P2 Infinite Health
FF4138:0909 Infinite Time
FF413A:000F Freeze Timer
FF4003:0063 Infinite Credits

[terpsfan101]

Fantasy Zone (Japan) (NES)

018E:09 Infinite Lives
0057:09 Infinite Gold (1 of 6)
0058:09 Infinite Gold (2 of 6)
0059:09 Infinite Gold (3 of 6)
005A:09 Infinite Gold (4 of 6)
005B:09 Infinite Gold (5 of 6)
005C:09 Infinite Gold (6 of 6)

[terpsfan101]

A few more MS/GG codes:

Wonder Boy III - The Dragon's Trap (USA, Europe) (Master System)
Monster World II - Dragon no Wana (Japan) (Game Gear)
Wonder Boy - The Dragon's Trap (Europe) (Game Gear)
Wonder Boy III - The Dragon's Trap (Europe) (Beta) (Game Gear)

00C240:80 Invincibility

Bare Knuckle II ~ Streets of Rage 2 ~ Streets of Rage II (World) (Game Gear)

00C383:xx Stage Modifier (xx=00-05)
00C389:01 Enable Infinite Health Cheat
00C389:00 Disable Infinite Health Cheat

Halley Wars (USA, Europe) (Game Gear)
Halley Wars (Japan) (Game Gear)

00C064:11 Go to Extra Options Menu (Enable on Title Screen, then disable)
00C065:01 Enable Invincibility Cheat
00C065:00 Disable Invincibility Cheat

Ys - The Vanished Omens (USA, Europe) (Master System)

3A9-29B-2A2 Infinite HP
2AE-ACC-6E2 Infinite Gold
09E-F2F-E66 Start a new game with $2536 Gold
13E-F2F-E66 Start a new game with $5096 Gold
27E-F2F-E66 Start a new game with $10216 Gold
FFE-F2F-E66 Start a new game with $65512 Gold
00C22A:FF Infinite/Max HP (1 of 2)
00C222:FF Infinite/Max HP (2 of 2)

[terpsfan101]

Some more GG/MS codes:

Impossible Mission (Europe) (Master System)

00C0CD:32 Freeze Timer
7E6-FBC-3B7 Infinite Time

Alex Kidd in Miracle World (USA, Europe) (Master System)
Alex Kidd in Miracle World (USA, Europe) (Rev 1) (Master System)

004-7EF-4C6 Infinite Money

Alex Kidd in Shinobi World (USA, Europe) (Master System)

00D-B0E-3BE Invincibility (after being hit) (blinking) (Disable to pick-up items)
040-028-E66 Start with 4 Health Units, instead of 3 (1 of 2)
040-44E-E66 Start with 4 Health Units, instead of 3 (2 of 2)
050-028-E66 Start with 5 Health Units (1 of 2)
050-44E-E66 Start with 5 Health Units (2 of 2)
060-028-E66 Start with 6 Health Units (1 of 2)
060-44E-E66 Start with 6 Health Units (2 of 2)
03D-EFE-E62 Start with 3 Lives, instead of 2
05D-EFE-E62 Start with 5 Lives
07D-EFE-E62 Start with 7 Lives
09D-EFE-E62 Start with 9 Lives

PGA Tour Golf II (USA, Europe) (Game Gear)

00DC2D:00 No Wind
00DC2D:0F Strong Wind
00DC2D:1F Massive Wind
00DC91:0A Golf bag holds 16 clubs plus putter, instead of 13 clubs
3E5-6FB-191 Almost No Wind (1 of 3)
005-70B-195 Almost No Wind (2 of 3)
185-71B-6EA Almost No Wind (3 of 3)
3E5-6FB-191 Strong Wind (1 of 3)
0F5-70B-195 Strong Wind (2 of 3)
185-71B-6EA Strong Wind (3 of 3)
3E5-6FB-191 Massive Wind (1 of 3)
1F5-70B-195 Massive Wind (2 of 3)
185-71B-6EA Massive Wind (3 of 3)
0AC-CCD-D5E Golf bag holds 16 clubs plus putter, instead of 13 clubs

Credit Galoob for Game Genie Wind Codes

PGA Tour Golf (Europe) (Master System)

006-D2D-19A Always on Same Stroke
3E7-27C-191 Strong wind (1 of 3)
0F7-28C-195 Strong wind (2 of 3)
187-29C-6EA Strong wind (3 of 3)
3E7-27C-191 Massive wind (1 of 3)
1F7-28C-195 Massive wind (2 of 3)
187-29C-6EA Massive wind (3 of 3)
017-55C-4CA Hit longer shots
FF7-55C-4CA Hit even longer shots

Credit Galoob for all codes

Golfamania (Europe) (Master System)
Golfamania (Europe) (Beta) (Master System)
Super Golf (Europe) (Beta) (Master System)

00C3D8:00 No Wind
00C3D8:0F Strong Wind
00C3D8:1E Massive Wind

Wimbledon (Europe) (Master System)

00C-73E-C45 CPU can't Score
00C-99E-C45 No Games scored by CPU
07C-98E-F7A Most Games are given to you
3A5-3B7-2A2 Infinite Attribute Points (Tour Mode)
141-804-D56 Start with 20 Attribute Points, instead of 15 (Tour Mode)
191-804-D56 Start with 25 Attribute Points (Tour Mode)
1E1-804-D56 Start with 30 Attribute Points (Tour Mode)
281-804-D56 Start with 40 Attribute Points (Tour Mode)
321-804-D56 Start with 50 Attribute Points (Tour Mode)
3C1-804-D56 Start with 60 Attribute Points (Tour Mode)
00CB22:3C Infinite Attribute Points (Tour Mode)
00C430:14 Max Speed (Tour Mode)
00C431:14 Max Power (Tour Mode)
00C432:14 Max Skill (Tour Mode)
00CB03:00 P1 Score is always 0
00CB03:01 P1 Score is always 15
00CB03:02 P1 Score is always 30
00CB03:03 P1 Score is always 40 (Next Point by P1 Wins Game, unless P2 has 40)
00CB03:04 P1 Score is always 40 Advantage (Next Point by P1 Wins Game)
00CB02:00 P2 Score is always 0
00CB02:01 P2 Score is always 15
00CB02:02 P2 Score is always 30
00CB02:03 P2 Score is always 40 (Next Point by P2 Wins Game, unless P1 has 40)
00CB02:04 P2 Score is always 40 Advantage (Next Point by P2 Wins Game)
00CB07:00 P1 Games Won is always 0
00CB07:01 P1 Games Won is always 1
00CB07:02 P1 Games Won is always 2
00CB07:03 P1 Games Won is always 3
00CB07:04 P1 Games Won is always 4
00CB07:05 P1 Games Won is always 5 (Next Game Won by P1 Wins Set, unless P2 also has 5 or 6 Games Won)
00CB07:06 P1 Games Won is always 6 (Next Game Won by P1 Wins Set)
00CB04:00 P2 Games Won is always 0
00CB04:01 P2 Games Won is always 1
00CB04:02 P2 Games Won is always 2
00CB04:03 P2 Games Won is always 3
00CB04:04 P2 Games Won is always 4
00CB04:05 P2 Games Won is always 5 (Next Game Won by P2 Wins Set, unless P1 also has 5 or 6 Games Won)
00CB04:06 P2 Games Won is always 6 (Next Game Won by P2 Wins Set)

Credit Galoob for CPU can't Score, No Games scored by CPU, and Most Games are given to you

Submarine Attack (Europe) (Master System)

054-D0D-E66 Start with 5 Lives, instead of 3
084-D0D-E66 Start with 8 Lives
0A4-D0D-E66 Start with 10 Lives

[terpsfan101]

Crystal Warriors (USA, Europe) (Game Gear)

7E1-C6A-3B7 Infinite HP - All Characters
7E5-29B-3B7 Infinite MP - In Battle - All Characters
7EF-ABC-3B7 Infinite MP - Outside Battle - All Characters
2AA-B88-6E2 Inns are Free (if you can cover the cost)
2AC-EA8-6E2 Fortunes are Free (if you can cover the cost)
2A7-428-6E2 Weapons, Armor, and Spells are Free (if you can cover the cost)

Phantasy Star (USA, Europe) (Rev 2) (Master System)
Phantasy Star (USA, Europe) (Rev 3) (Master System)

7E5-C9E-3B7 Infinite HP (only tested on Alis)
1AE-ABE-A22 Infinite MP - In Battle (only tested on Alis)
1AE-58E-A22 Infinite MP - Outside Battle (only tested on Alis)
2AC-09D-6E2 Infinite Meseta

[terpsfan101]

Some more MS/GG codes:

Deep Duck Trouble Starring Donald Duck (Europe) (Master System)

C90-E75-E69 Invincibility
057-0BF-E66 Start with 5 Health Units, instead of 3 (1 of 2)
054-4EE-E66 Start with 5 Health Units, instead of 3 (2 of 2)
0A7-0BF-E66 Start with 10 Health Units (1 of 2)
0A4-4EE-E66 Start with 10 Health Units (2 of 2)
0F7-0BF-E66 Start with 15 Health Units (1 of 2)
0F4-4EE-E66 Start with 15 Health Units (2 of 2)
057-06F-E66 Start with 5 Lives, instead of 3
097-06F-E66 Start with 9 Lives
257-06F-E66 Start with 25 Lives
507-06F-E66 Start with 50 Lives
757-06F-E66 Start with 75 Lives
997-06F-E66 Start with 99 Lives

credit mezmorize for Invincibility

Urban Strike (USA, Europe) (Game Gear)

B67-9CA-3BE Infinite Lives
4E6-AEA-2AF Infinite Armor and Guns (1 of 2)
466-B0A-2AB Infinite Armor and Guns (2 of 2)
7E6-C0A-3B7 Infinite Fuel, Missiles, and Rockets
006-FCA-3BE Infinite Time
05A-D5C-E66 Start with 5 Lives, instead of 3
09A-D5C-E66 Start with 9 Lives
19A-D5C-E66 Start with 25 Lives
32A-D5C-E66 Start with 50 Lives
4BA-D5C-E66 Start with 75 Lives
63A-D5C-E66 Start with 99 Lives

Frogger (USA) (Proto) (Game Gear)

050-01E-E66 Start with 5 Lives, instead of 3
080-01E-E66 Start with 8 Lives
0A0-01E-E66 Start with 10 Lives

Galaga 2 (Europe) (Game Gear)

05C-12B-E66 Start with 5 Lives, instead of 3 (Enable before Title Screen)
07C-12B-E66 Start with 7 Lives (Enable before Title Screen)
09C-12B-E66 Start with 9 Lives (Enable before Title Screen)

Galaga '91 (Japan) (Game Gear)

05C-06B-E66 Start with 5 Lives, instead of 3 (Enable before Title Screen)
07C-06B-E66 Start with 7 Lives (Enable before Title Screen)
09C-06B-E66 Start with 9 Lives (Enable before Title Screen)

Berlin no Kabe (Japan) (Game Gear)

00C01C:09 Infinite Lives
00C01D:09 Infinite Time (1 of 2)
00C01E:99 Inifnite Time (2 of 2)
00C01F:00 Freeze Timer
3AF-4BE-2A2 Infinite Lives
006-0FF-3BA Infinite Time

Sonic The Hedgehog - Triple Trouble (USA, Europe) (Game Gear)
Sonic & Tails 2 (Japan) (Game Gear)

00D14B:0A Infinite Continues

Lemmings 2 - The Tribes (Unknown) (Proto) (Master System)

00E-D24-3BE Infinite use of all types of lemmings
00C-C7F-3BA Infinite Time
00C4B5:63 Infinite Slot 1 Lemmings
00C4B6:63 Infinite Slot 2 Lemmings
00C4B7:63 Infinite Slot 3 Lemmings
00C4B8:63 Infinite Slot 4 Lemmings
00C4B9:63 Infinite Slot 5 Lemmings
00C4BA:63 Infinite Slot 6 Lemmings
00C4BB:63 Infinite Slot 7 Lemmings
00C4BC:63 Infinite Slot 8 Lemmings
00C509:3C Infinite Time (1 of 2)
00C50A:09 Infinite Time (2 of 2)
00C50B:00 Freeze Timer
00C52A:08 Always have 8 Lemmings to Save
00C52B:08 Always have 100% Lemmings Saved (Set value to however many Lemmings you have to save)

Lemmings 2 - The Tribes (Unknown) (Proto) (Game Gear)

00D-374-3BE Infinite use of all types of lemmings
00C-99F-3BA Infinite Time
00C4B5:63 Infinite Slot 1 Lemmings
00C4B6:63 Infinite Slot 2 Lemmings
00C4B7:63 Infinite Slot 3 Lemmings
00C4B8:63 Infinite Slot 4 Lemmings
00C4B9:63 Infinite Slot 5 Lemmings
00C4BA:63 Infinite Slot 6 Lemmings
00C4BB:63 Infinite Slot 7 Lemmings
00C4BC:63 Infinite Slot 8 Lemmings
00C529:3C Infinite Time (1 of 2)
00C52A:09 Infinite Time (2 of 2)
00C52B:00 Freeze Timer
00C54A:08 Always have 8 Lemmings to Save
00C54B:08 Always have 100% Lemmings Saved (Set value to however many Lemmings you have to save)

[terpsfan101]

Here's another batch of MS/GG codes:

Sonic The Hedgehog 2 (Europe) (Master System)

3A8-82C-2A2 Invincibility (after being hit)
3A7-DFC-2A2 Don't Lose Rings when Hit
009-30F-3BE Infinite Lives
000-A9D-3BA Infinite Time
008-98B-3BA Infinite Time Underwater
052-5CD-E66 Start with 5 Lives, instead of 3
072-5CD-E66 Start with 7 Lives
092-5CD-E66 Start with 9 Lives
222-92D-2A2 Start with some Rings most of the Time

Sonic The Hedgehog 2 (Europe) (Rev 1) (Master System)

3A8-84C-2A2 Invincibility (after being hit)
3A7-DAC-2A2 Don't Lose Rings when Hit
009-30F-3BE Infinite Lives
000-A9D-3BA Infinite Time
008-BAB-3BA Infinite Time Underwater
052-5CD-E66 Start with 5 Lives, instead of 3
072-5CD-E66 Start with 7 Lives
092-5CD-E66 Start with 9 Lives
222-92D-2A2 Start with some Rings most of the Time

Psycho Fox (USA, Europe) (Master System)

00C24D:02 Infinite Invincibility Potion Time (disables Music)

Gain Ground (Europe) (Master System)

00A-F7E-3BE Infinite Lives - Both Players
B62-60E-3BE Infinite Time
058-2DE-E66 Start with 5 Lives, instead of 3 - Both Players
078-2DE-E66 Start with 7 Lives - Both Players
098-2DE-E66 Start with 9 Lives - Both Players
00CDE7:09 P1 Infinite Lives
00CE27:09 P2 Infinite Lives
00CFE3:3C Freeze Timer

Gangster Town (USA, Europe) (Master System)

7EA-32D-3B7 Infinite Health - Both Players
00C0A5:10 P1 Infinite Health
00C0A8:10 P2 Infinite Health

Sonic The Hedgehog - Triple Trouble (USA, Europe) (Game Gear)
Sonic & Tails 2 (Japan) (Game Gear)

00D17E:05 Have all Chaos Emeralds

Ms. Pac-Man (USA) (Game Gear)

3A5-E08-2A2 Infinite Lives - 1P Game - Half Screen View
3A6-0E8-2A2 P1 Infinite Lives - 2P Game - Half Screen View
3A6-228-2A2 P2 Infinite Lives - 2P Game - Half Screen View

Note that the previous Infinite Lives Game Genie codes that I posted only work with the Zoom (Default) view

Master of Darkness (Europe) (Master System)

052-857-E66 Start with 5 Lives, instead of 3
092-857-E66 Start with 9 Lives
192-857-E66 Start with 25 Lives
322-857-E66 Start with 50 Lives
4B2-857-E66 Start with 75 Lives
642-857-E66 Start with 100 Lives

Power Strike (USA, Europe) (Master System)

05C-E0F-E66 Start with 5 Lives, instead of 3
08C-E0F-E66 Start with 8 Lives
0AC-E0F-E66 Start with 10 Lives

Aleste (Japan) (Master System)

05A-CBF-E66 Start with 5 Lives, instead of 3
08A-CBF-E66 Start with 8 Lives
0AA-CBF-E66 Start with 10 Lives

Wonder Boy - The Dragon's Trap (Europe) (Game Gear)

00F-D4E-A29 Hit Anywhere - Dragon mode
00F-23E-C49 Hit Anywhere - Other Modes (1 of 3)
00E-9CE-2A2 Hit Anywhere - Other Modes (2 of 3)
37E-CEE-196 Hit Anywhere - Other Modes (3 of 3)

credit nolberto82

Mortal Kombat (Europe) (Master System)

20B-06F-F7A Punches do more damage
2CB-26F-C42 Most kicks do more damage
30B-86F-C42 Foot sweeps do more damage
30B-2EF-D5A Flying punches do more damage
33B-56F-A2E Uppercuts do more damage
2AF-1A7-D5A Throws do more damage
2BB-76F-F7A Sonya Blade's leg grab does more damage
2BB-66F-F7A Scorpion's harpoon does more damage
2BB-6EF-F7A Rayden's flying thunderbolt does more damage
2BB-4EF-D56 Johhny Cage's shadow kick does more damage
37B-36F-D52 Some other special moves do more damage
023-E44-C4E Each round is 29 seconds
043-E44-C4E Each round is 49 seconds
063-E44-C4E Each round is 69 seconds
01B-AAA-E6A Start on match 2
02B-AAA-E6A Start on match 3
03B-AAA-E6A Start on match 4
04B-AAA-E6A Start on match 5
05B-AAA-E6A Start on mirror match
06B-AAA-E6A Start on endurance match 1
07B-AAA-E6A Start on endurance match 2
08B-AAA-E6A Start on endurance match 3
09B-AAA-E6A Start on match against Goro
0AB-AAA-E6A Start on match against Shang Tsung

credit Galoob for all codes

Lucky Dime Caper, The (USA, Europe) (Game Gear)

370-EAB-A29 Hammer Hits Anywhere

credit nolberto82

Rastan (USA, Europe) (Master System)

00C020:F0 Infinite Health
00C021:F0 Max Health
C9E-7E7-E69 Invincibility
00C-29E-3BE Infinite Continues
968-2BE-7FB Start a new game with 1.5x Health (1 of 2)
968-2FE-7FB Start a new game with 1.5x Health (2 of 2)
C88-2BE-7FB Start a new game with 2x Health (1 of 2)
C88-2FE-7FB Start a new game with 2x Health (2 of 2)
F08-2BE-7FB Start a new game with Max Health (1 of 2)
F08-2FE-7FB Start a new game with Max Health (2 of 2)

Rastan Saga (Japan) (Game Gear)

00C020:F0 Infinite Health
00C021:F0 Max Health
C9E-827-E69 Invincibility
00C-D2E-3BE Infinite Continues
A58-9EE-5D3 Start a new game with 1.5x Health
DC8-9EE-5D3 Start a new game with 2x Health
F08-9EE-5D3 Start a new game with Max Health