21 Building · Space Sim games your group can play together online, including Starlathe, Astro Colony, and Outlive 25.
All games: 21
Command your ship and fleet in a galaxy that truly lives: 150 sectors where six factions mine, haul, trade, build and wage war whether you're there or not. Trade it, rob it, defend it — or forge your own fleet and carve out your place in it. Play solo or in online co-op.
Astro Colony throws you into an endless Universe of exploration, automation and survival! Build interconnected colonies, alone or with friends, and turn planets into thriving industrial hubs! Design conveyor systems and take care of your Astronauts as you expand your intergalactic empire!
Build your base, prepare your troops, and face your most epic battle yet in this old-school real-time strategy game. Choose between two factions, test your skills in three epic campaigns and engage in online battles with up to 16 players simultaneously.
Terraform a dead planet back to life in this open world survival crafting game. Explore ruins, gather resources, print machines, drive modular vehicles, grow forests, biomes, and ecosystems. Create life and make it thrive with your own hands.
Build physically simulated rovers to transport awkwardly shaped cargo across the rugged terrain of Mars. Earn funds, unlock new parts, and use your ingenuity to help the Martians establish a new home. Playable solo or in online co-op!
Gather resources, craft components, build vehicles, and code their logic in a physics-driven engineering sandbox and full scale space sim.
Stellar Settlers is a chill space base/city builder and colony sim game. With unique vertical and horizontal base-building gameplay, settle on 10 hostile alien planets and build your own thriving colony. Get enough materials to build a physics-based Spaceship and try to escape from disasters.
The RTS/FPS phenomenon has moved into space! Build your base on an asteroid, command fleets of starships for epic battles, pilot fighters, mine and trade resources, assemble robots to defend or assault other stations. Take sole command or share the glory as you fight for control of the quadrant.
Design and simulate the starships of your dreams! Command your ship or fleet in epic battles and manage your crew while exploring a dangerous galaxy. Play alone or with friends, test your ships in online PvP, and let your imagination reach for the stars!
Pixel Starships is an FTL-style online sci-fi strategy builder and management game with a competitive PVP tournament. Set in the retro galaxy, your role is to explore space, meet aliens, and develop your ship, crew and AI. The game contains deep strategic and 4x elements. PSS is community-driven.
Build and explore in a true space sandbox survival adventure. Construct mighty capital vessels, sprawling planetary settlements, and vast space stations in your galactic journey to discover the mysteries of Empyrion!
A procedural co-op space sandbox where players can build their own space ships out of dynamically scalable blocks. Fight epic space battles, explore, mine, trade, wage wars and build your own empire to save your galaxy from being torn apart by an unknown enemy.
Mine and craft your way to orbit, build your own starship and explore a vast, dangerous galaxy alongside your crew. For players who love a meaningful survival progression, a unique and elegant building system, and epic space-opera scale.
Command the Nimbatus and craft drones out of hundreds of different parts. Survive unknown threats in a fully destructible, procedural universe, compete against other players in different arenas or enjoy complete creative freedom in the sandbox.
Interstellar Rift is an open world starship simulator with an emphasis on ship construction and multi-player interaction. Survive in a hostile galaxy with your own custom designed and constructed starship. Invite other players to join your crew or fight them across the galaxy!
Share a Creative or Survival world in Space Engineers, where your group turns mined resources and block-by-block ideas into ships, bases, and missions.
Andromeda is a hybrid between a Space 4X and an MMO. An online universe sandbox with 2 galaxies full of planets to colonize. Build structures like Mines to generate resources to build ships and engage in fleet battles with NPCs and other players, or just sit and chat with the friendly community.
Build ships, stations, and factions with friends in StarMade’s online voxel sandbox. Create your own goals across a generated universe, with server-based co-op and PvP.
Use the Nimbatus Drone Creator to construct physically simulated drones and try them out in a virtual testing environment. Do you have what it takes to become a drone engineer?
Race across the terraformed surface of Mars in your Skimmer, a completely customizable hover racing vehicle. Piloting skill and engineering make the difference between winning and losing in Vector 36, a Physics-Based Racer. Available with and without VR or HOTAS.
Millions of players worldwide have flown, built, and fought their way through Captain Forever. CF Trilogy brings Captains Forever, Successor, and Impostor to Steam with a beautiful new renderer, new modules, and a reimagined world written by acclaimed novelist Cassandra Khaw.