I'm sharing my first effort on this thread. I decided to learn ASM, and ended up coding something silly and unnecesary: difficulty levels to Super Metroid. With this, the Item Cancel setting becomes a difficulty selection menu. The levels roughly follow the same rules as the GBA games and AM2R. Basically, apply this and you have three new game modes for your game.

Oh, also, the event flag 0xF0 is applied automatically whenever you start a hard game so you can have alternate room states for it.

Technical info:

The patch is fairly simple but hijacks many existing routines across many banks. The idea was that no value was to be changed, only scaled according to the difficulty level, to make it more compatible with other hacks (unless your hack heavily modifies or moves existing routines, see the readme for more info on what is changed).

I've broken the source into several files to give a (fake) semblance of modularity. In most cases each file corresponds to a different bank and a specific behavior that is changed, so you can tweak it (or erase parts) however you want to make it compatible with your hack.

I've also included three samples that are applied by default, just as a proof of concept. One edits some rooms in order to add more enemies if Hard mode is selected, the other tweaks some enemies to have different behavior on Hard, and the other adjusts some vanilla values to make it more consistent with the rest of the series. This was done only for demonstration purposes and should be disabled if you plan to use this seriously.

This is my first ASM ever, so if this interests you feel free to drop feedback or edit the sources however you want (but give credit if you use it (: ).