Single-player games like Outpost: Infinity Siege
Below are 15 single-player Steam games similar to Outpost: Infinity Siege, 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 Outpost: Infinity Siege page.
Ranked picks
- 1
Per Aspera
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Strategy with Outpost: Infinity Siege.
Make Mars your own! Take control of the world’s most sophisticated AI (AMI) and terraform the surface of the Red Planet for a city-building experience on a planetary scale. Transform this barren world into a lush paradise and explore the surface for any ancient secrets that may be waiting.
- 2
Roboden
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Strategy with Outpost: Infinity Siege.
Roboden is a fresh take on the RTS genre: less micro-control tedium with more units!
- 3
The Riftbreaker
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
The Riftbreaker is a solo or Co-op base-building, survival game with Action-RPG elements for up to 4 players. Hack & slash countless hordes of enemies. Build up your base, craft powerful weapons and research new inventions to survive.
- 4
Out of Ammo
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
Out of Ammo is an intense VR Tower Defense / FPS hybrid strategy game that will have you constructing defenses, calling in artillery, issuing orders, and taking direct control of your soldiers in order to survive a relentless enemy onslaught.
- 5
Mindustry
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Strategy with Outpost: Infinity Siege.
An open-ended factory management game with RTS and tower defense elements.
- 6
Vectorio
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
Build. Automate. Defend.
- 7
Golemworks
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Strategy with Outpost: Infinity Siege.
A strategic fusion of automation game and tower defense
- 8
Armed to the Gears
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
Control a fully armed Mech and fight through cyberpunk cities, military bases and industrial ruins. Capture and defend territories, build turrets and structures, and wage war against powerful enemies!
- 9
Orcs Must Die!
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
Slice them, burn them, skewer them, and launch them - no matter how you get it done, orcs must die in this fantasy action-strategy game from Robot Entertainment.
- 10
The Last Spell
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
Defend the last bastion of humanity with your squad of heroes! Exterminate fiendish monsters with magic and brute force by night and re-build your battered city defenses by day in this tactical RPG with rogue-lite mechanics.
- 11
RimWorld
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Strategy with Outpost: Infinity Siege.
A sci-fi colony sim driven by an intelligent AI storyteller. Generates stories by simulating psychology, ecology, gunplay, melee combat, climate, biomes, diplomacy, interpersonal relationships, art, medicine, trade, and more.
- 12
Diplomacy is Not an Option
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
Diplomacy is Not an Option is a strategy game set in a medieval fantasy world. Build your town and defenses, raise huge armies and fight against massive hordes of enemies. How long can you survive?
- 13
Cataclismo
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Strategy with Outpost: Infinity Siege.
Design and build fortresses brick by brick to stand against endless hordes of Horrors in this real-time strategy game with resource management, siege defense, and exploration. Lead from the ramparts, push back the darkness, and hold fast against the creatures of the Mist.
- 14
From Glory To Goo
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Strategy with Outpost: Infinity Siege.
From Glory To Goo is a Sci-Fi survival RTS set on an alien world. Serve as humanity's bulwark by establishing a colony and supporting your colonists still in orbit. But beware, for The Goo, a relentless and shape-shifting force approaches from all sides, even above and below.
- 15
Project Morpheus: Prologue
Single-player alternative to Outpost: Infinity Siege — playable solo, no multiplayer required. Shares Action and Strategy with Outpost: Infinity Siege.
Welcome to Project: Morpheus, you will reprise yourself as EAST, and play your way in this world where reality and dreams collide.