nah, ibeat him using only Rain's water attack, lifting him in the air at the upper corner then firing another one the moment i'm free. yes iknow it doesn't answer your question

actually I found one on my own. Just wait in the corner and uppercut him when he makes a move. I beat it with Stryker, Sindel, Sheeva, Cyrax, and basically everyone else I suck with easilly. ....now time to move up a ladder

Yeah, make sure you duck, and upper cut most of the time. If you don't Shao Khan appears impossible to kill sometimes.

I found a way with Sheeva. Do her teleport move, and just uppercut or combo repeatedly. Khan will either block or accept the hit. Either way, if he blocks, this will put a small space in between you two, and will allow you to fall out the air with Sheeva again. You just gotta time it quick.

Keep trying. Other than that duck when he air charges and attack when side charges.

Sub-Zero or Sindel would be the best choices, imo.

Shao Kahn seems to be highly vulnerable to Subby's freeze ball, and Sindel's pretty handy while she's flying. With her, just fly backwards and spit out some purple puff power. Works for me.