From a narrative point of view, I'd have to say Spec Ops: The Line, in no small part because it BEGAN as a bog-standard, typical military shooter, complete with crisp jargon between team mates and your squad mowing down all sorts of faceless foes. I actually had to be talked into playing this game because I typically look at shooters as a bit of a 'meh' proposition, something that began maybe five or six years ago. (*EDIT* Looking back, I think it might actually be even longer, which makes me feel kind of old. -_- ) Used to really enjoy Halo, Gears, Call of Duty Zombies, etc, but eventually just kind of lost interested in shooters that weren't Bioshock, and REALLY lost interest in military shooters.
Anyway, long story short, blew me away. The varied ways the 'final scene' could end, the subtle ways your progression changed yourself and your teammates, from their in-combat dialogue to execution animations, it was just absolutely nuts the detail that had been given. It was worth another playthrough literally just to catch details I had missed the first time around, easily left a bigger impression on my brain than any game since the original Bioshock.
Mechanically? Ironically I'd have to say Sunset Overdrive, and that's despite the fact that I've only played a little of it. x3 I dunno, something about the means of traversal, mixed with the extensive weaponry you can obtain, and even the fourth-wall breaking irreverence, it just seems like a game that was designed from day-one to be... well, the Deadpool movie. =P Only presumably with less nudity and swearing.
(Infamous: Second Son comes in a very close second, as I do think that Sunset Overdrive edges it out, in my opinion, in both weaponry and traversal variety, while Infamous edges it out in terms of characters and narrative. Still love it to pieces, though.)
Zanten, Doer Of The Things
Unless He Forgets In Which Case Zanten, Forgetter Of The Things
Or He Procrascinates, In Which Case Zanten, Doer Of The Things Later
Or It Involves Moving Furniture, in Which Case Zanten, F*** You.







