My husband is an avid gamer. He said he would not even consider letting our "possible son" (pregnant) play this game until he turned 15.
He said in the game you go back and forth in time. When you are in present day, there is a fair amount of language.
And when you are an assasin of course you are killing ppl. He said it is very gory.
He said he might allow an 11 year old to play T rated games, but that there are plenty of good E rated games out there.
I can say that I have watched some of these M rated games being played and they DEFINITELY earn thier rating.
Honestly, I don't even like my husband to play some of them.
He also said that the gaming systems themselves have websites w/ tons of game info on them.
I hope that helps.