Secrets that weren't discovered in games for years

[dlevere]

Today, we're taking a look at some video game secrets that stayed hidden for years at a time — decades in some cases.

Some of these secrets are hidden Easter eggs that reveal more about the plot, some are random glitches that are most likely throwbacks to earlier builds of a game.

Many found traction from fans digging around in the source code.

Regardless of where they come from, these are secrets that stayed out of the limelight for years after the game released.

[Phil The Hammer]

Something along the line of your OP: NES Zelda 1 went for years without any "one-hit-kill" code being found. I hacked such codes, & it was unbelievably easy - simply find the enemies' health value & lower it to zero. That made any weapon that could harm a given enemy deliver one-hit kills. Thus, the boomerang becomes a deadly weapon!

I know that wasn't an "Easter Egg", but it was astounding to me, with all the hundreds of codes hacked for that game over 30 years, that no one had found those super-easy-to-make codes!