Since you guys are going with the 'safe' choices, I'd say Prototype 1 and 2 myself. You have free reign in New York City, jack Tanks and Choppers, destroy zombie-like creatures AND humans, it has a air of mystery in it, and the campaign story is extremely good. However, it has no multiplayer, and the campaign CAN get boring after a few playthroughs. Free Play however, applies to your inner demon as you can kill everyone in sight, destroy military bases, kill the rapid response forces after your asses, then disguise as one of them for the shits and giggles.