Single-player games like Moon Mystery
Below are 14 single-player Steam games similar to Moon Mystery, 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 Moon Mystery page.
Ranked picks
- 1
Within the Cosmos
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
Within the Cosmos is a sci-fi RPG. After awakening in a secluded star system, you soon discover a fractured human society grappling with an emerging android threat. Explore planets, uncover mysteries, and navigate differing philosophies. Your choices will shape how the story unfolds.
- 2
HELIOBIOTIC
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
Explore the floating islands of a ruined alien world, unearthing the secrets of its lost civilization in a fast-paced time loop.
- 3
Call of Duty®: Infinite Warfare
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
Infinite Warfare delivers three unique game modes: Campaign, Multiplayer, and Zombies.
- 4
Alien Life Lab
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
Giedi Satellite takes a job as a wildlife handler on a colossal nature preserve space station that goes awry in comedic and horrific fashion. Become an Alien Wildlife Control Specialist in this horromedy adventure.
- 5
Humanity Lost
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
Will you save humanity? You are on a mission to find a new planet for humans to inhabit. In this story driven FPS space opera you will explore open world planets, find weapons, upgrade your character, and befriend alien species.
- 6
Atomic Heart
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
In a mad and sublime utopian world, take part in explosive encounters. Adapt your fighting style to each opponent, use your environment and upgrade your equipment to fulfill your mission. If you want to reach the truth, you'll have to pay in blood.
- 7
Moons of Madness
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Adventure with Moon Mystery.
Moons of Madness is a first-person, story-driven cosmic horror game where the scientific exploration of Mars meets the supernatural dread of Lovecraft.
- 8
Syndrome
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
Syndrome, a sci-fi survival horror game that places you in a living hell inside a doomed starship. Find out what happened to your lost crew. Run. Hide. Fight. Survive.
- 9
Portal
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action with Moon Mystery.
Portal™ is a new single player game from Valve. Set in the mysterious Aperture Science Laboratories, Portal has been called one of the most innovative new games on the horizon and will offer gamers hours of unique gameplay.
- 10
Half-Life
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action with Moon Mystery.
Named Game of the Year by over 50 publications, Valve's debut title blends action and adventure with award-winning technology to create a frighteningly realistic world where players must think to survive. Also includes an exciting multiplayer mode that allows you to play against friends and enemies around the world.
- 11
Deliver Us The Moon
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
The Moon has gone dark, cutting off Earth’s last source of energy. As a lone astronaut, you’ll explore abandoned lunar bases, solve intricate puzzles, and navigate stunning zero-gravity environments. Operate advanced vehicles, uncover hidden truths, and survive in this gripping sci-fi thriller.
- 12
Titanfall® 2
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action with Moon Mystery.
Respawn Entertainment gives you the most advanced titan technology in its new, single player campaign & multiplayer experience. Combine & conquer with new titans & pilots, deadlier weapons, & customization and progression systems that help you and your titan flow as one unstoppable killing force.
- 13
Starfield
Single-player alternative to Moon Mystery — playable solo, no multiplayer required.
Starfield is the first new universe in 25 years from Bethesda Game Studios, the award-winning creators of The Elder Scrolls V: Skyrim and Fallout 4.
- 14
Red Matter 2
Single-player alternative to Moon Mystery — playable solo, no multiplayer required. Shares Action and Adventure with Moon Mystery.
Red Matter 2 is an immersive, puzzle-adventure game that will transport you to the far reaches of space. Step into the shoes of Sasha, an agent awakened in a lunar base by an undercover operative and tasked with uncovering the secrets of the mysterious Red Matter.