Co-op games like Radioactivity
Below are 8 cooperative Steam games similar to Radioactivity, ranked by player overlap and content similarity. Every pick supports cooperative play — online co-op, LAN co-op, or shared/split-screen — so you can play with friends right out of the box. imho.run pulls from the same Steam category data Valve uses internally, so "Co-op" here matches what the store labels.
Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Radioactivity page.
Ranked picks
- 1
Echoes Afterfall
Online Co-op alternative to Radioactivity — playable with friends. Shares Action and Adventure with Radioactivity.
Team up in a chilling co-op experience, delving into procedurally generated backroom style buildings. Survive together or succumb into the Echoes.
- 2
Backrooms: The Others
Online Co-op alternative to Radioactivity — playable with friends. Shares Indie and Adventure with Radioactivity.
Backrooms: The Others is a cooperative horror game for up to 4 players where you will be forced to explore these unknown nooks and crannies, trying to survive in this complex world where death can be waiting for you at every turn!
- 3
Backrooms: The Next Level
Online Co-op alternative to Radioactivity — playable with friends. Shares Indie and Adventure with Radioactivity.
Backrooms: The Next Level is a Co-op horror game up to 4 players, where you and your friends will explore the game, try to pass the game level using your mind, wit, remembering the places where you were
- 4
PILGRIM
Online Co-op alternative to Radioactivity — playable with friends. Shares Action and Indie with Radioactivity.
Pilgrim is a medieval-based, co-op horror, adventure. Can you and your friends make it to the end of The Road?
- 5
The Refuge
Online Co-op alternative to Radioactivity — playable with friends. Shares Action and Indie with Radioactivity.
Serve the A.R.C organization. Infiltrate infested zones, complete contracts, and extract with your resources. Upgrade your facilities and complete quests to unlock new services. An intense PvE extraction where the difficulty increases with your ambitions.
- 6
MISERY
Online Co-op alternative to Radioactivity — playable with friends. Shares Action and Indie with Radioactivity.
MISERY is a 1–5 player co-op survival game set in a nuclear disaster zone. Here, every day is a struggle: search radioactive ruins for resources, build your bunker, craft weapons, and explore a weird, procedurally-generated world with your friends. Beware of anomalies, monsters, and armed bandits.
- 7
Junk Survivor
Online Co-op alternative to Radioactivity — playable with friends. Shares Action and Indie with Radioactivity.
Junk Survivor is a zombie post-apocalypse game where you loot, craft, build and farm in a struggle to survive. With a vast map to explore, a robust skillset to unlock this customizable sandbox awaits the adventurer. How long before you die!
- 8
Backrooms Lost Runners
Online Co-op alternative to Radioactivity — playable with friends. Shares Action and Indie with Radioactivity.
Backrooms Lost Runners is a co-op survival horror with team play, voice-reactive AI, and immersive puzzles. This isn’t a “walking simulator”: explore liminal spaces, outsmart entities, and remember—even a whisper can give you away.