How about Postal or Postal 2, both very violent games, you can use a cat as a silencer! - and that is just one of the many things you could do, you could also piss on people! What other game can you do that in!? none
But what about Dead Rising? That game featured full-body dismemberment of ZOMBIES with dual Mini-Chainsaws obtained from a psycho clown / childrens entertainer, who was killed by falling on his OWN chainsaws! Come On Gamesradar, You're Slipping.
The idea of Mass Effect 2 is a great one, but very ambitious, what if it goes to hell? and why would you play as Shepard if you made your own character in the first Mass Effect game, so if you keep your originally designed character, and he bites the dust in Mass Effect 2, will you be playing as Shepard in Mass Effect 3?
What other game can you do that in!?
none