oh, and i made the code for blue, and time and darkness because I'm that much of a patcher.
I'd do it for red but i don't know the memory addresses for it or how action replay codes are structured on gba so that's outside my league i guess. my blue code might be able to give hints.

i put it on projectpokemon a while ago

today in reminiscing with pinkolol - spring edition: so mystery dungeon works in turns. Every action is a turn including walking.
Someone made an 'infinite steps' code for the game which they obviously didn't test because turning the value to FFFF will just cause the dungeon to explode the moment you move

Instead, what you want to do, is loop an amount of steps. The game starts at 1000 or 500 steps and counts down, so as long as it never reaches 0, you can keep going forever.

But if you freeze the value, enemies won't spawn. So you need it to stay in a loop of at least 1 step, so that enemies can continue spawning.

This ends up resulting to about 2 extra lines compared to the original code

by the way my ds broke so it'll be a while before I get to experience this again.
once i do i'm releasing the infinite steps mystery dungeon code that SHOULD'VE been released instead of the one most people are using. For all the DS games.
Tis depicts the fun experimenting I had to do to find step and money variables in the games I play on that system and laughing as they corrupt my save files a million times