...on normal. I've never been bad at fighting games, and I've always been pretty good at MK. I don't get it. I just cannot beat him. I tried the advice I found on here - i.e. spam low fireballs, if he gets in close, xray, but my fireballs don't do s*** and he gets close a lot more frequently than my xray gets full. He also usually corners me. I die because he spams spears + hammers at me constantly. I usually duck under the spears, but can't react in time to jump the hammers, if I plan on attacking at all.
I don't main liu kang, but I didn't have a lot of trouble with him beating Shao Kahn. For most characters, jumping over kahn sometimes leaves him open to a combo/attack. This is a good opening for a bicyle kick/combo to add to the fireball spamming. Hope it helps.
When I get desperate to beat him I spam Flying Kick, Bicycle Kick. i mostly use flying kick, if he taunts or if you got a good feeling go for bicycle otherwise flying kick if he blocks it i instantly go for upper cut and if its a good idea ill throw in a jumping kick or 2
In the words of Shao Kahn "You Suck!" haha sorry :P lol
Here's by far the best way to beat him, disregard the other things you've read. Press 'Triangle', 'Square', then 'X'- this results in him bouncing off the floor from the third hit, after doing that combo 3 times finish with an uppercut. Ridiculously easy spam combo that does 10 hits and a good amount of damage. I used this, beat him first try.