Free games like Underground Security Inc
Below are 9 free-to-play Steam games similar to Underground Security Inc, ranked by player overlap and content similarity. No purchase or Steam login required to view the list. Every pick is a full free-to-play title — not a demo, trial, or time-limited giveaway. imho.run's catalogue refreshes daily, so newly free or newly popular titles surface here without manual editing.
Want the full alternatives list (paid + free + Steam Deck + cheaper picks)? See the parent games like Underground Security Inc page.
Ranked picks
- 1
Outpath: First Journey
Free-to-play alternative to Underground Security Inc — no purchase or trial window. Shares Indie with Underground Security Inc.
Outpath: First Journey is a prologue chapter of the main game, Outpath. An experimental clicker base building game. Craft, gather & manage resources, build your base and buy more islands to exploit and expand!
- 2
Die in the Dungeon: Origins
Free-to-play alternative to Underground Security Inc — no purchase or trial window. Shares Strategy and Indie with Underground Security Inc.
Fight your way through a mysterious dungeon in this deck-building, turn-based roguelike game where you don't use cards, but DICE! Deal with enemies by combining dice on your board, boost their effects with magical relics, and discover the story behind Die in the Dungeon!
- 3
The Riftbreaker: Prologue
Free-to-play alternative to Underground Security Inc — no purchase or trial window. Shares Strategy and Indie with Underground Security Inc.
The Riftbreaker: Prologue allows you to experience the events taking place before the story campaign of the main game. Explore an entirely new world. Gather resources. Build up a base. Defend yourself from thousands of alien creatures.
- 4
Shape of Dreams: Prologue
Free-to-play alternative to Underground Security Inc — no purchase or trial window. Shares Indie with Underground Security Inc.
《Shape of Dreams: Prologue》is a unique game that blends action roguelite with MOBA-style gameplay. Edit your character's Memories to create your own champion. Face all challenges alone or play with friends in up to 4-player co-op.
- 5
Muck
Free-to-play alternative to Underground Security Inc — no purchase or trial window. Shares Indie with Underground Security Inc.
Muck is a survival-roguelike. Collect resources, find items & build a base to survive for as long as you can.
- 6
Limbus Company
Free-to-play alternative to Underground Security Inc — no purchase or trial window.
As the Executive Manager of Limbus Company, lead your group of twelve Sinners, venture into the buried facilities of Lobotomy Corporation, and lay claim on the Golden Boughs.
- 7
Umamusume: Pretty Derby
Free-to-play alternative to Underground Security Inc — no purchase or trial window.
Umamusume: Pretty Derby, winner of Best Mobile Game at The Game Awards 2025, is ready to race! Scout featured trainees and supporters as you navigate the immersive sports life simulation through the game's in-depth training system and top-of-the-line 3D graphics!
- 8
AdVenture Capitalist
Free-to-play alternative to Underground Security Inc — no purchase or trial window. Shares Indie with Underground Security Inc.
Welcome, eager young investor, to AdVenture Capitalist! Arguably the world's greatest Capitalism simulator!
- 9
坍塌世界
Free-to-play alternative to Underground Security Inc — no purchase or trial window. Shares Strategy and Indie with Underground Security Inc.
"Collapsing World" is an innovative tower defense game blending deck-building and roguelike mechanics. Recruit unique companions, craft powerful skill decks, and tackle randomized stages. Deep strategy breaks the traditional TD mold—every run is a fresh challenge!