Free games like Ostranauts
Below are 8 free-to-play Steam games similar to Ostranauts, ranked by player overlap and content similarity. No purchase or Steam login required to view the list. Every pick is a full free-to-play title — not a demo, trial, or time-limited giveaway. imho.run's catalogue refreshes daily, so newly free or newly popular titles surface here without manual editing.
Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Ostranauts page.
Ranked picks
- 1
Paper Lily - Chapter 1
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Indie and RPG with Ostranauts.
Paper Lily is an RPG horror game in which you can solve puzzles in different ways. Explore a hidden world, meet strange characters, and guide Lacie as she attempts to find answers about her unusual condition.
- 2
Project Kat - Paper Lily Prologue
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Indie and RPG with Ostranauts.
Project Kat is a short, unconventional RPG horror game in which there is always another way. Solve puzzles, make friends (or not), and guide Kat as she attempts to uncover the mystery behind a strange golden letter.
- 3
SuchArt: Creative Space
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Indie and Simulation with Ostranauts.
Paint on any surfaces with numerous tools in Creative Space — a free sandbox version of SuchArt: Genius Artist Simulator. Create masterpieces, complete commissions, and decorate your studio in the most advanced artist sim!
- 4
Crime Scene Cleaner: Prologue
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Simulation with Ostranauts.
When there’s a call, you are the man to clean up after your client’s dirty job. Siding with the mafia is a dangerous game, but they pay well, and you need money, right? So take your mop and better remove those bloodstains quickly before the police come.
- 5
The Riftbreaker: Prologue
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Indie with Ostranauts.
The Riftbreaker: Prologue allows you to experience the events taking place before the story campaign of the main game. Explore an entirely new world. Gather resources. Build up a base. Defend yourself from thousands of alien creatures.
- 6
The Last Sovereign
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Indie and RPG with Ostranauts.
Explore a world torn between armies of lust and purity in which everything is more complex than it seems, deciding the fate of nations through might, politics, and finance. Every decision matters in an intricate saga that tracks thousands of variables.
- 7
The Test: Secrets of the Soul 2
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Indie and Simulation with Ostranauts.
You will answer questions that will reveal things deep within. Some will be uncomfortable, but with great knowledge comes great sacrifice. Can you make it all the way through The Test, and are you SURE you want the answers you seek? For it is time to once again unlock "Secrets of the Soul..."
- 8
SCP – Containment Breach
Free-to-play alternative to Ostranauts — no purchase or trial window. Shares Indie with Ostranauts.
A procedural first-person horror adventure. You are on your own after something goes terribly wrong in this top-secret containment facility. Collect items to aid in your escape and try to uncover the truth, as horror lurks behind every door. Can you make it out alive?