I've played every version of every game since the first one and have experienced and seen some broken crap. Many characters had infinites or OP vortex/resets so this is kind of a tough call but I made my choice based on ease of use/minimal effort required to wreck someone regardless of who they use.
I say MKT Noob Saibot. There was no meter, no guessing, no setup....I just had to hit you once or hit you once with a disabler and that was the round, not to mention doing his combo was easy as hell. I even taught noobs how to do it (no pun intended....maybe
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