I have many games, ranging from sports to strategy and the Assassin's Creed games have always been my go-to games when I am in need of a game that I can get involved and get lost in.
The graphics, are really good and the game allows you to explore and do things as you see fit. There is still a storyline to follow as you unlock certain sections of the map but it will never push you to do those things.
The controls are easy to follow too and overall a great game.

I just wish there were more Assassin's Creed games on the Mac.