There was already a thread about Mortal Kombat on Ps2 and all, you might wanna check
this out.
I have bought the game and I love it, there is soo much to unlock it, and you will not be able to do it if you rent it, this game is to own, seriously. Ok yeah 1 fatality per character, but still those one are pretty damn good ones. I still have to unlock many other characters to check theirs out.