Credit to SmileUser96 & sylandro.

Replaces the auto item cancel option with a difficulty switch.
Auto=hard/Manual=normal

Includes sprite replacements (if you don't like, make your own or ask how to).
Modifies drop values (no drop rate).
Bypasses auto item cancel check. (6 bytes free)
Spike damage values (idk needs its own damage check for now).
Armor & damage division vs. enemies. (uses 2 bytes ram, $7EFFFE)
Display difficulty on file select screen. (these sprites are easy to change..).
Save & Load (does not modify the actual save & load routines).

Just check all the free spaces used.
Feel free to post modifications.

UPDATE:
New hotstuff.asm contains code for heat damage, lava, & acid.

UPDATE:
Added spikes.asm. Old routine only did one additional damage.
New one uses one less byte, includes the 60 damage spike.
Very easy to tweak if 120 damage is too much for you.

UPDATE:
Added skipintrosaveswork.asm.
All three save files will now work. This is compatible with all hacks.
Be careful with the hotstuff.asm, free space needs to be $8DFFF1.
If you did patch, & your game crashes during the escape, it's cause it overwrote one byte.
06FFF0 needs to be FF. Crisis averted.