Single-player games like Calcium Contract
Below are 12 single-player Steam games similar to Calcium Contract, 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 Calcium Contract page.
Ranked picks
- 1
Zortch
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action and Indie with Calcium Contract.
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
- 2
MeowGun: Hell Denizen
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action and Indie with Calcium Contract.
A fast paced silly cutegore FPS! Earth has been taken over by demons. A catgirl codenamed MeowMeow fights back! MEOW, GUN, CLAW and BLOW UP hordes of evil demons, zombies, and other monsters in colorful environments with tons of weapons! The game runs on the FTEQW engine.
- 3
HELLBREAK
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action and Indie with Calcium Contract.
HELLBREAK is a fast-paced roguelite, survivor-like FPS where you fight through escalating waves in brutal arenas in Hell. Build powerful loadouts, earn favor from demon lords to unlock new gear, and climb the leaderboards for your salvation.
- 4
Guns and Nuns: Storming Hell
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action with Calcium Contract.
Demons are not the danger, YOU ARE THE DANGER!!! play as Angelica Amadeus, a nun with the power of faith and guns. Slay demons at your heart's content on bizarre stages with strange gravity fields. Get highscores to unlock more stages and weapons and teach those filthy demons their place.
- 5
ODDCORE
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action and Indie with Calcium Contract.
You have only 5 minutes to stylishly explode your way through the hordes of corrupted entities in a retro FPS, roguelike liminal-nightmare... and Timmee is here to help!
- 6
WRATH: Aeon of Ruin
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action with Calcium Contract.
Blast, slice and shred through your enemies in this hardcore FPS inspired by the icons of the '90s, powered by the legendary Quake-1 Tech. Taking place in a realm left to rot, take up arms, unearth long-forgotten secrets and hunt down the Guardians of the Old World.
- 7
Herald of Havoc
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action and Indie with Calcium Contract.
Grab huge guns, mow down hundreds of enemies, reach the end of the level, repeat. It doesn't get any simpler than this. Embark on a 3 hour campaign with varied environments and situations, and beat the leaderboard on a tightly crafted survival mode.
- 8
AMID EVIL
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action and Indie with Calcium Contract.
A retro FPS for the ages! Once branded a HERETIC. Now YOU have been chosen as our champion! Reclaim our sacred weapons. Take back our ancient lands. If you can stand... AMID EVIL.
- 9
Redneck Rampage
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action with Calcium Contract.
Well, we crash-landed that UFO in the desert and Bubba says he wants to go home. Heck, I don't blame him 'cause there ain't no place like Hickston. But according to my map, we're gonna have to blast our way through jack o' lope farms and a riverboat as well as a brothel 'fore we get home again.
- 10
DOOM
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action with Calcium Contract.
Now includes all three premium DLC packs (Unto the Evil, Hell Followed, and Bloodfall), maps, modes, and weapons, as well as all feature updates including Arcade Mode, Photo Mode, and the latest Update 6.66, which brings further multiplayer improvements as well as revamps multiplayer progression.
- 11
HROT
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action and Indie with Calcium Contract.
HROT is a single-player retro FPS set in a small socialist country neighboring Soviet Union (Czechoslovakia) after an unspecified disaster in 1986. Those times were dark and terrifying and so is the game.
- 12
PO'ed: Definitive Edition
Single-player alternative to Calcium Contract — playable solo, no multiplayer required. Shares Action with Calcium Contract.
PO’ed is an adrenaline-pumping space shooter that features gameplay elements inspired by generational powerhouses DOOM and QUAKE. Play as a chef who crashlands on an alien planet infested with extraterrestrial foes. Using a menu of “household” weapons, PO’ed puts your wits and reflexes to the test.