Single-player games like UNDEFINED
Below are 13 single-player Steam games similar to UNDEFINED, 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 UNDEFINED page.
Ranked picks
- 1
Linelight
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
Linelight is an elegant puzzle game set in a world of lines.
- 2
Cat Quest
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
The multi award-winning Action RPG. Some say 'Diablo with Cats' others a 'Super-cute Skyrim', whatever your take, Cat Quest's loot-fuelled cat-venture is as beautifully crafted, as its combat and magic are ultra-satisfying. Universally adored by critics - it'll have you purring for joy!
- 3
Plebby Quest: The Crusades
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
Survive ambitious rulers dreaming of an empire, outsmart treacherous neighbors longing to burn your spoils, and navigate the religion’s predictably unreasonable demands; you need ask only one question as you build your legacy – “Will you burn them, or be burnt?”
- 4
Monaco: What's Yours Is Mine
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
Monaco: What's Yours Is Mine is a single player or co-op heist game. Assemble a crack team of thieves, case the joint, and pull off the perfect heist.
- 5
Pikuniku
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
Pikuniku is an absurdly wonderful puzzle-exploration game that takes place in a strange but playful world where not everything is as happy as it seems. Help peculiar characters overcome struggles, uncover a deep state conspiracy, and start a little revolution in this delightful dystopian adventure!
- 6
Bladed fury
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
An action game set in the Ancient China, bringing players addictive experiences with its unique Chinese traditional art-style and sound design.
- 7
Lair of the Clockwork God
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
A fast-paced Point-and-Click adventure AND an indie platfomer in one! Join adventurer Ben and wannabe indie darling Dan in a race against time to stop all the Apocalypses happening at the same time.
- 8
Semblance
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
Semblance is an innovative platformer with deformable terrain, set in a beautiful minimalist world. It’s a game that asks, what if you could deform and reshape the world itself? Semblance takes the idea of a ‘platform’ in a platformer and turns it on its head.
- 9
Deep Space
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
You are entrusted with the role of one of the elite captains, put on a high-tech mech suit suitable for travel into space and go on an exciting journey.
- 10
The Lost Dungeon Of Knight
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
The Lost Dungeon Of Knight is a first-person adventure game with puzzle elements.
- 11
Curse of the dungeon
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
You have to explore amazing places to get to the secret secrets of your soul.
- 12
Adventure Galaxy
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Indie and Adventure with UNDEFINED.
Adventure Galaxy - an indie game with a first-person view, the game takes place on a space station in space.
- 13
Night Darkness
Single-player alternative to UNDEFINED — playable solo, no multiplayer required. Shares Action and Indie with UNDEFINED.
You have to take control of one of the most famous mercenaries and complete a special mission to save humanity from certain death.