ESRB would probably rate Toribash as M+ or Ao+ (Lol Odlov :P), but quite frankly,
not many give a crap about the age ratings, and neither do i. I mean, seriously,
i'm willing to bet that i'm not the only one who played Doom 1/2 at an age of
3-5 years. Far from it.
As for the age group, well, probably teens, but that doesn't eliminate the fact
that there are (much) younger/older people playing it, and having fun too.
A good game should appeal to a very broad audience, and that's what Toribash does :0