A good game with a basis for historical research
As the title of the games shows - this is about assassin's. That means that violence and killing are definitely part of the game. I would start out playing the game with your child to make sure that they know that this is not reality. The majority of children already know this, but it's good to make sure.
A lot of the buildings and people are taken from real life. What they actually are has been changed for the games. But it is a good learning experience to look up to see if the buildings were real and if the people were real and if they really did do the things that the games show. For instance the Auditore family, including Ezio, were not real. The Borgia's were definitely real, as were Machiavelli and Leonardo di Vinci. But their actions in this game did not (for the most part) take place.
Ezio does not kill the innocent. He kills only what he is supposed to kill, and if the player misses and acidently kills an innocent, the game states that Ezio did not kill the innocent. If more innocents are killed the memory will restart. In fact, in the games he comes to the aid of women and children that need help. The programmers, also, gave him a great sense of humor.
Some other reviewer mentioned the paintings. These were done by the Painter Raphael. They are considered classics. This would be another learning experience for both parents and children. Finding out who Raphael was, where he lived and what the period was like. In Assassin's Creed II, there were a lot of Classics done by various artists.
Another learning experience is that the Templar's were not, in real life, the bad guys, and the term hashishiyya or hashishi as used by Muslim sources is used metaphorically in its abusive sense (i.e. "irreligious social outcasts", "low-class rabble", etc.). "The literal interpretation of this term in referring to the Nizaris (as hashish consuming intoxicated assassins) is rooted in the fantasies of medieval Westerners and their imaginative ignorance of Islam and the Ismailis. These supposedly medieval fantasies were still in vogue as late as 1990 until the publication of the ground breaking book on the Ismailis by the Twelver Shia author and researcher in original documents in Arabic and Persian that had been discovered in the late 20th century concerning the Ismailis in general and the Nizari Ismailis in particular. (This citation is from Daftary, Farhad (1990). The Ismailis: Their history and doctrines. Cambridge, England: Cambridge University Press. Page 13)
The two sides in this game were not, in reality, rivals or enemies. It's just that you cannot have a game without good guys and bad guys. So creative license has been taken in order to make a very good game.
This title contains:
Violence & scariness