Single-player games like Once Upon The Universe
Below are 8 single-player Steam games similar to Once Upon The Universe, ranked by player overlap. Every pick carries Steam's Single-player category, so multiplayer-only titles or always-online games don't sneak in. imho.run pulls the category data from Steam directly — Single-player here matches what the store labels.
Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Once Upon The Universe page.
Ranked picks
- 1
Galactic Simulator2: Stargate
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
Galactic Simulator 2: Stargate is a roguelite simulation game inspired by the Fermi Paradox and the Great Filter. Pilot your ship, gather resources, build stargates, and discover other civilizations as you explore an ever-evolving galaxy.
- 2
Inspiral: Echoes of Gravity
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
Start as an asteroid, grow by absorbing other celestial bodies to become a planet, a star, and ultimately a black hole. Experience realistic gravity and orbital physics in an ever-evolving sandbox universe.
- 3
The Fermi Paradox
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
The Fermi Paradox is a choice-driven sci-fi narrative strategy game in which your decisions in one corner of the galaxy can upend entire civilizations in another. Guide species through millennia and help them explore the vastness of space, make contact and, perhaps, create harmony.
- 4
Space Haven
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
Embark on a space voyage with your ragtag crew of civilians in search of a new home. Build spaceships tile by tile, create optimal gas conditions, manage the needs and moods of their crew, encounter other space-faring groups, and explore the universe in this spaceship colony simulation.
- 5
Solar Expanse - Space Exploration Manager
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
Explore the Solar System. Mine and drop asteroids. Colonize and terraform. Lead the space race and compete with other corporations on your way to profit. Watch the expansion of human race over the centuries.
- 6
Celestial Command
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
Mine asteroids, salvage space debris, design your own small or massive spacecraft using individual functional components, complete missions, and engage in battles against enemies in a vast galaxy with realistic physics based on orbital mechanics or in a classic physics mode.
- 7
Interstellar Pilot 2
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
The hit mobile game Interstellar Pilot 2 has come to Steam. Join the TEF forces heading to the Gatopean sector to find a new home for mankind. Play how you like in this open world space-sim developed by Pixelfactor.
- 8
Dyson Sphere Program
Single-player alternative to Once Upon The Universe — playable solo, no multiplayer required. Shares Strategy and Indie with Once Upon The Universe.
Build the most efficient intergalactic factory in space simulation strategy game Dyson Sphere Program! Harness the power of stars, collect resources, plan and design production lines and develop your interstellar factory from a small space workshop to a galaxy-wide industrial empire.