Best free to play open world multiplayer games on steam

Team Fortress 2

Nine distinct classes provide a broad range of tactical abilities and personalities. Constantly updated with new game modes, maps, equipment and, most importantly, hats! 

Players rating: very positive 

Fistful of Frags

Fistful of Frags is Multiplayer based, first person enabled, action packed and skill demanding shooter set in the Wild West times. A unique combination of non stop action and slow but powerful weaponry.

players rating: very positive

WildStar

Critically acclaimed and now Free to Play, WildStar is a fantastical sci-fi MMO where you can join your friends or undertake your own epic adventures on the fabled planet Nexus! 

Players rating: very positive

Marvel Heroes 2016

Marvel Heroes 2016 is the premier Marvel MMO-ARPG that you have been waiting for! Play as the Avengers, Guardians of the Galaxy, X-Men and more. Battle infamous villains such as Dr. Doom, Loki, Magneto to save the universe. 

Players rating: very positive

Gotham City Impostors

Gotham City Impostors is now Free to Play! Join the Batman "helpers" or junior Jokerz in the streets of Gotham full of bullets, bodies, and bear traps. 

Players rating: very positive

Defiance

Join the futuristic online open-world shooter where thousands of players scour a transformed Earth competing for alien technology Hunt alone or with others as you improve your skills and level up, unlocking powerful weapons that will help you survive the  massive battles that await. 

Players rating: Mostly positive

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