Played for about 2 hours, and I am loving the game so far. Stealth gameplay is incrediably satisfying (among the best I have ever played so far), and the game seems flexible enough to allow for more of an action approach for people who aren't huge stealth fans as well. Combat is also flexible enough to switch between stealth and a more action oreiented aproach on the fly. AI is very challenging so far on hard, and the game makes you pay for sloppy execution. Visually the game isn't the best from techical standpoint, but the art style is gorgeous and unique.
Haven't got powers yet so the game should get even better from here. From what I have played so far if your a fan of games like Hitman, Deus Ex, Thief, and Bioshock this game is right up your alley. Also from what I played so far there is a ton of side stuff to collect, without even getting to any of the side missions yet, so I don't think length will be a problem if you are a completionist. It basically took me 2 hours just to get through the prologue, as I was making sure I didn't miss anything.
Just a note for stealth players, the lean function is paramount for effective stealth in this game.
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