Just don't ask to get stuff that is illegal to get and I think it is fine.

OK cool. Thanks man. So how about it? I know how to do the Dead Pool Uppercut and the person who wins is in the Dead Pool. But what else can you do with it? And more importantly, how?

Later

I played the "Version 9.1" hack in an actual MKII cabinet, at this comic store back in the day. Off the top of my head, I remember this game having:

-red shadow kick for Johnny cage (super-long range)
-Jax's grab and punch move was super fast and made Liu Kang noises
-you could get Noob in like 12 or 6 wins (i forget which) instead of 50

I know there was more weird stuff but it slips my mind at the moment.

Challenger hack does weird stuff like making Kintaro the second opponent you fight. And I think there are question marks all over the CPU opponent ladder.

The mame history file refers to Liu Kang's "Red Dragon" and Kung Lao's "Bones in the hat" fatalities but to this day I have no clue if that's BS or what.