Of the many fighting game franchises out there, I think Mortal Kombat is my favorite. One of the first games I played, after Sonic 2 on the Game Gear, was Mortal Kombat 2 (also for the Game Gear). I also played Mortal Kombat Trilogy on the Playstation.
What's your favorite Mortal Kombat game? Mine is, as I just mentioned, Mortal Kombat Trilogy. But Mortal Kombat 9 comes in at a close second for the awesome story mode and storyline.