Single-player games like NUCLIDEAN
Below are 8 single-player Steam games similar to NUCLIDEAN, 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 NUCLIDEAN page.
Ranked picks
- 1

Serious Sam: Siberian Mayhem
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action and Adventure with NUCLIDEAN.
Serious Sam: Siberian Mayhem is a new stand-alone expansion to the world of the classic FPS series. Join the fight against Notorious Mental on a journey through the wild lands of Russia, and find your way through this lost chapter of Sam Stone's adventures.
- 2

Anomalous
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action with NUCLIDEAN.
A SHORT and sweet pixelated low fidelity 90s throwback hyper-fast action shooter. Survive and fight through a city overrun with manufactured monstrosities, biomass horrors, and a military authority trying to purge everything living. Heavy metal / techno soundtrack featuring BOD Music
- 3

Zortch
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action and Adventure with NUCLIDEAN.
Meet Zortch Maxinum: short order cook, amateur engineer and professional slacker; Bored and tired of her day job she decides to go on a holiday but alas she picks a cheap option: turns out it's a scheme by aliens who capture humans to eat their brains! also this game is a sci-fi horror comedy fps
- 4

CULTIC
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action with NUCLIDEAN.
Death is only the beginning. Crawl from your grave and gear up to fight your way through the ranks of a mysterious and twisted cult. You, your guns, and your dynamite will have to shoot, slide, blast, duck, dodge, and maybe throw a gib or two to survive in this old-school-inspired shooter.
- 5

Chasm: The Rift
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action with NUCLIDEAN.
Prepare for terror in this ground-breaking classic old-school FPS. Following the destruction of Time you are left to battle in this horrific hellhole of multilevel interconnected missions populated by gruesome grotesque creatures.
- 6

DOOM II
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action with NUCLIDEAN.
Hell has invaded Earth, and to save it, you must battle mightier demons with even more powerful weapons. This beloved sequel to the groundbreaking DOOM (1993) introduced players to the brutal Super Shotgun, the infamous Icon of Sin boss, and more intense FPS action.
- 7

Golden Light
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action and Adventure with NUCLIDEAN.
Eat weapons, be scared and question your own mind in this Survival-Horror FPS Prop Hunt Roguelike about meat. Walls are watching you!
- 8

DEAD TRASH
Single-player alternative to NUCLIDEAN — playable solo, no multiplayer required. Shares Action with NUCLIDEAN.
Years into a brutal lockdown, a once-thriving city lies in ruins, abandoned by its government and overrun by vicious, mindless infected. Grab your hammer, collect your nerves and enter the mayhem.