Co-op games like Online: 404
Below are 8 cooperative Steam games similar to Online: 404, 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 Online: 404 page.
Ranked picks
- 1
Zombase
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Adventure with Online: 404.
Zombase is a co-op zombie survival game where your base is your escape plan. Build wheels, propellers, weapons, and traps onto your mobile base, then fight through the horde and try to reach the safe zone without crashing.
- 2
Zombie Defense:Breach of The Undead
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Indie with Online: 404.
A dark wave-based zombie defense game where you build your defenses, fight relentless undead hordes, and survive against the infected… and hostile raiders?
- 3
Soviet Survival
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Adventure with Online: 404.
Soviet Survival is an isometric, open-world survival game where you must find your place in the ruined Soviet Union.
- 4
VEIN
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Simulation with Online: 404.
VEIN is a post-apocalyptic survival multiplayer sandbox game. Gather supplies to survive, explore abandoned buildings, defend your home, and rebuild society, whether alone or with friends.
- 5
Infect Cam
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Indie with Online: 404.
A world where the living envy the dead. Cities are plunged into darkness, the world into silence. You are part of the extraction team, but this time you are trying to save not just people, but humanity itself. Gear up, trust your comrades, and dive into the darkness to save humanity!
- 6
DREADZONE
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Indie with Online: 404.
Dreadzone is a survival game set in a deadly quarantine zone. Scavenge for resources, craft tools, build shelter, and survive against dangerous animals, zombies, mutants, and other survivors. Explore the zone where desperation drives everyone to do whatever it takes to survive.
- 7
Ars Notoria
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Adventure with Online: 404.
Ars Notoria is an open-world survival crafting game set in a rich fantasy world. Learn six distinct schools of magic, gather resources, build your base, expand your influence, and stand against the ever-shifting threat of the Enthralled. You are the one destined to change the kingdom.
- 8
MISERY
Online Co-op alternative to Online: 404 — playable with friends. Shares Action and Indie with Online: 404.
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.