What game have you played most (in hours)?

War Thunder, Payday 2.

Ghost Recon Phantoms - 342 hrs. I'm hooked on Payday 2 lately tho, 73 hours and counting

Terraria at 180. But i have a lot of games to spread out my time okay. And half-life WON has to have sucked up much more hours than that with mods.

Europa Universalis IV, 297 hours

Minecraft is my my current top at over 3000 hours. The next most played game for me is Battlefield 3 at 621 hours, although I suspect BF4 to have overtaken it by now.

Jagged Alliance 2, I'm playing it since 2001 :)

Guild Wars 2 - 5651 and still counting.

Diablo II -- Estimated 7000-10000 hours from about 2002-2012
Path of Exile -- 4019 hours on Steam + ~1000 hours on open beta.
Terraria -- 1856 hours on Steam + ~300 hours on a "DRM free" version before I bought the game.

Other games with 1K+ hours:
Elder Scrolls V: Skyrim (XBox 360 + Steam)
Elder Scrolls IV: Oblivion (XBox 360 + Steam)
Elder Scrolls III: Morrowind (XBox + "DRM free" + Steam)
Fallout: New Vegas (XBox 360 + Steam)

My life- 219145 hours and counting

Dota 2: 1000
Battlefield 3: 700

TF2 with like 2162 hours, although most of it is idling

Borderlands 2- 200+ hours

WoW = dont know how many hours
Planetside 2 = 500+ hours on steam, dont know how many hours in planetside client

Battlefield 3 - Over 400 hours logged
Darksiders II - 55 hours
Borderlands - 32 hours (But this will increase because I just bought the 4 DLCs)
Insurgency - 25 hours

See for yourself lol ^^

3.2k Dota
350 PoE

The only games that log time are in Steam so here goes

DOTA 2 47hrs
MW2 40hrs
CS GO: 39 hours

Yeah, I'm busy with... stuff

Guild Wars 2 313 hours

Not much time spent on steam games, but I probably had over 3k in WoW

Diablo II with over 3500 hours. (You lose count after five years or so....)

Neverwinter Nights would be next with about 2500 hours. Then Left 4 Dead 2.with about 1500 hours.

WoW ! No idea how much time but way over 2000 hours

Dota 2 376h

Garry's Mod - 1099 hrs

Out of the games I can keep track of? DOTA 2 at 876h, followed by Civ 5 (138) & Killing Floor (100). I would guess that I've spent far more time in Ultima Online though, which I played between 1999 & 2005.