Steam published their Best of 2017 on Steam that categorizes the 2017 sales performance of games by top sellers, top new releases, top VR games, and top Early Access graduates and games with most simultaneous players. Below the best sellers for 2017, these are in fact in a random order as Steam does not disclose what holds the number one spot.
H1Z1
Rocket League
The Witcher III: Wild Hunt
PLAYERUNKNOWN'S BATTLEGROUNDS
Rainbow Six: Siege
ARK: Survival Evolved
Dota 2
Tom Clancy's Ghost Recon: Wildlands
Warframe
Grand Theft Auto V
Counter-Strike: Global Offensive
Divinity: Original Sin II
