Nine: Dishonored
I'm not normally a fan of stealth games, but Dishonored's ambitions in other respects caught my attention quite happily. Its asymmetrical morality was one of the most ambitious attempts at managing ethics in games since the original Fallout, while its steampunk setting aligned it more with the literary genre to great affect. But it was also a great game, particularly in its middle sections, where exploration, stealth, story, and character progression aligned quite neatly, making it entertaining for all kinds of different players in all kinds of different ways.