What is the playtime difference between your most played game and second most played game?

Crusader Kings II - 655h
Dota2 - 435h

3540.6h - AirMech
1816.5h - Team Fortress 2
1648.6h - Firefall
991.0h - Trove
449.8h - Borderlands 2
358.3h - Dota 2

22,968h (957 days) - World of Warcraft {Added every character by total play time}

Darkest dungeon around 1100h
Civ V around 900h

300

Path of Exile and the rest. :D

579h Realm of the Mad God (but i also played in the browser so its probably ~800h)
385h Counter-Strike: Global Offensive

Borderlands 2 - 302 hrs (Likely to increase because I'm replaying it with my brother)
Fallout: New Vegas - 117 hrs

Difference: 185 hrs

4 hours. Or 69.
Torchlight II - 147 hrs
Divinity: Original Sin - 143 (Enhanced Edition) + 73 (Classic) hrs

almost 500 hours

Jagged Alliance: Back in Action - 119 hours (probably the only person in the world that has this game as most played)
Crusader Kings II - 113 hours (soon to be in first place)

outside Steam:
310 hours - Witcher 3 on GOG Galaxy (around 285 hours for first gameplay with DLCs, now replaying on hardest difficulty)

outside Steam, GOG, Origin etc...
Gothic 1, 2 and 3 - around 1 million hours :D Just kiddin, but surely much more than 300 :D

Team Fortress 2- 2793 hrs
Chivalry- 483 hrs

Difference= 2310 hrs

Haven't touched TF2 for long while but I'm currently loving Overwatch.

Rocket League
633 hrs on record

The Witcher 3: Wild Hunt
137 hrs on record

So - 496 hours!