71%Strong matchGTFO
87%44k87% positive reviews, Very Positive across 44k reviews·Horror · FPS
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Gamma Strain is an intense third-person co-op horror shooter. Gear up, create unique builds and synergies, and battle terrifying creatures. Teamwork, tactics, and flawless execution are key to your survival.
Gamma Strain
Steam
Gamma Strain is a cooperative third-person horror shooter. Battle through hordes of different types of mutated anomalies, customize your character and gear, and level-up as you try to contain this ever-growing threat. Teamwork, tactics, and flawless execution are key to your survival.


If your squad dies, you’ll have to restart. (permadeath). When you restart your new mission is shown but ALSO the location of the previously fallen squad is shown. You can choose to go to the fallen squad location and retrieve their digital biometric dog tags and potential gear. If you do this- the XP that that squad gained is added to your XP upon a successful extraction. If you die on this run, then you lose everything. When you restart the game, the prior fallen squads are no longer shown.


Choose to extract or continue. Increasing the potential rewards, but simultaneously increasing the potential risk. Players can choose to continue playing and get more loot and XP, or play it safe and end the run. If you wipe, no XP is gained. High Risk. High Reward.


Operators can only go into "the zone" ONCE. Similar to the protocols developed during the Chernobyl incident. These protocols limit exposure, due to the unknown and potential contamination risks. That means each time a fresh squad is sent in. There is no individual Operator progression, but rather Class Progression.


When a squad member is downed and not revived in time, they are dragged away to the next nearest nest. They can be rescued before they are assimilated, but time is a factor. If all soldiers are downed, they are all taken to the nest, and the game session is over. “Game over, man. Game over.”
Steam data © 2026 Valve Corporation. Trademarks are property of their respective owners.
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