Sure, Bungie left us hanging like a bad wingman at a bar at the end of this one, but there's no denying that the second in the trilogy brought some exciting moments to the series—including, of course, online multiplayer. The introduction of the game on Xbox Live would go on to influence gaming's next step in hardware, demanding that consoles provide online capabilities like friend lists, lobbies, and chat. And really, this alone warrants a spot on this list.