Single-player games like Galaxy Union
Below are 9 single-player Steam games similar to Galaxy Union, 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 Galaxy Union page.
Ranked picks
- 1
Stellaris
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
Explore a galaxy full of wonders in this sci-fi grand strategy game from Paradox Development Studios. Interact with diverse alien races, discover strange new worlds with unexpected events and expand the reach of your empire. Each new adventure holds almost limitless possibilities.
- 2
Sid Meier's Civilization®: Beyond Earth™
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
Sid Meier’s Civilization: Beyond Earth is a new science-fiction-themed entry into the award winning Civilization series. As part of an expedition sent to find a home beyond Earth, lead your people into a new frontier, explore and colonize an alien planet and create a new civilization in space.
- 3
ENDLESS™ Space 2
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
ENDLESS™ Space 2 is a Strategic Space Opera, featuring the compelling “just one more turn” gameplay, set in the mysterious ENDLESS™ Universe. As the leader of your civilization, will you impose your vision and build the greatest stellar empire?
- 4
Sins of a Solar Empire®: Rebellion
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
Command a space-faring empire in Sins of a Solar Empire: Rebellion, the new stand-alone expansion that combines 4X depth with real-time strategy gameplay.
- 5
Galactic Civilizations III
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
Build a civilization that will stand the test of time in the largest space-based strategy game ever! Choose from dozens of unique races and make a name for yourself across the galaxy through diplomacy, espionage, technological advances, and more.
- 6
Nexus 5X
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
eXplore, eXpand, eXploit, eXterminate, EXPRESS. All of the depth, diplomacy, conflict and conquest of a turn-based 4X epic but played in fast-paced 60-minute competitive sessions. Play Solo or Multiplayer for 2-8 players.
- 7
Age of Wonders: Planetfall
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
Age of Wonders: Planetfall is the new strategy game from Triumph Studios, creators of the critically acclaimed Age of Wonders series, bringing all the exciting tactical turn-based combat and in-depth empire building of its predecessors to space in an all-new, sci-fi setting.
- 8
Master of Orion
Single-player alternative to Galaxy Union — playable solo, no multiplayer required. Shares Strategy with Galaxy Union.
The ascendant spacefaring 4X strategy game returns! A new chapter in the epic Master of Orion saga is poised to once again capture the imaginations of millions of gamers.
- 9
Desktop Hacker
Single-player alternative to Galaxy Union — playable solo, no multiplayer required.
A narrative driven hacking game that takes you on a journey around murky hacking circles. You will be using the console and graphical tools to hack systems in order to profit and advance the storyline.