ROBOCRAFT is described as 'Build insane Robot Battle Vehicles that drive, hover and fly; add weapons from the future and jump in the driving seat as you take them into battle in a team based capture the base Free-to-Win MMO'. There are eight games similar to ROBOCRAFT for a variety of platforms, including Windows, Mac, Linux, Steam and Playstation. The best alternative is Crossout, which is free. Other ROBOCRAFT like games are War Thunder (Freemium), World of Tanks (Freemium), World of Warships (Freemium) and Procelio Game (Free).
Crossout is a massively-multiplayer game of mechanic combat in a post-apocalyptic world. Craft your own battle machine from scores of interchangeable parts and drive them into combat with other players in online PvP battles.
Procelio is a multiplayer sandbox game where you build a robot out of modular parts, put guns on it, and go fight other people online. Procelio attempts to create a well polished game which players of all skill levels can enjoy.