Free Outbreak Sim Games on Steam

Steam currently has 267 Outbreak Sim games available to download and play. Explore our list of the best free games ranked by popularity and ratings. Data for this list is calculated from reviews and player counts reported directly by Steam and will be updated in real-time. Free Outbreak Sim game rankings were last updated on 7/29/2025.

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1. State of Survival

Survive the Zombies War in this RPG game of Apocalypse and Survival

State of Survival banner

State of Survival holds the #1 spot for "best free Outbreak Sim game on Steam" with a Player Score of 56. Its score was calculated by analyzing a total of 422 reviews on Steam. This breaks down to a total of 239 positive reviews and 183 negative reviews — making it "Mixed" on Steam.

It can be played and ran on Windows systems. At the moment, it is not possible to play or run State of Survival on the Steam Deck.

Release Date 8/2/2023
Developer FunPlus International AG
Publisher FunPlus International AG
Steam App Id 2485460

2. Post-Apo Builder: Prologue

Discover a post-apocalyptic world Collect resources and manage people Build your colony on the remains of an oil tanker Prepare supplies and vehicles for a dangerous expedition. Complete challenging tasks from the council of elders

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Post-Apo Builder: Prologue has achieved a Player Score of 66, placing it in the #2 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 430 reviews on Steam. This breaks down to a total of 298 positive reviews and 132 negative reviews — making it "Mixed" on Steam.

It can be played and ran on Windows systems. At the moment, it is not possible to play or run Post-Apo Builder: Prologue on the Steam Deck.

Release Date 8/2/2023
Franchise G-DEVS Games
Developer Septarian Games
Publishers
Steam App Id 2130380

3. 防疫英雄

这是一款休闲益智类游戏。根据经典的PVZ类游戏的核心玩法的基础上,创新题材,创新无尽模式。

防疫英雄 banner

防疫英雄 has achieved a Player Score of 60, placing it in the #3 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 89 reviews on Steam. This breaks down to a total of 57 positive reviews and 32 negative reviews — making it "Mixed" on Steam.

It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.

Release Date 6/23/2022
Developer LLz郦郦汁
Publisher LLz郦郦汁
Steam App Id 2014390

4. Plane Accident: Prologue

Dive into the heart of aviation mysteries in "Plane Accident: Prologue." Explore realistic crash sites, analyze evidence, and solve puzzles. Unveil the truth in this thrilling prelude to the full "Plane Accident" experience.

Plane Accident: Prologue banner

Plane Accident: Prologue has achieved a Player Score of 63, placing it in the #4 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 46 reviews on Steam. This breaks down to a total of 32 positive reviews and 14 negative reviews — making it "Mixed" on Steam.

It can be played and ran on Windows systems. At the moment, it is possible to play Plane Accident: Prologue on the Steam Deck (though some functionality may be limited).

Release Date 1/18/2024
Franchise Duality Games
Developers
Publishers
Steam App Id 2104670

5. Zombie Siege City

Grab your weapon, enjoy the thrill of zombie shooting, and don't stop firing until every last zombie is... well and truly dead. Earn rewards for your efforts, unlock new weapons, upgrade existing ones, and exterminate as many walking dead as possible.

Zombie Siege City banner

Zombie Siege City has achieved a Player Score of 61, placing it in the #5 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 96 reviews on Steam. This breaks down to a total of 62 positive reviews and 34 negative reviews — making it "Mixed" on Steam.

It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.

Release Date 11/2/2024
Developer STAR WORKS COMPANY LIMITED
Publisher STAR WORKS COMPANY LIMITED
Steam App Id 3116530

6. Life on the Edge

Life on the Edge is an educational tower defense game. You play as a cell struggling to survive waves of bacteria and the COVID-19 virus. Protect your cell and build an understanding of cell biology at the same time!

Life on the Edge banner

Life on the Edge has achieved a Player Score of 80, placing it in the #6 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 93 reviews on Steam. This breaks down to a total of 84 positive reviews and 9 negative reviews — making it "Very Positive" on Steam.

It can be played and ran on both Windows and Mac systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.

Release Date 6/17/2022
Developer LOTE Team
Publisher LOTE Team
Steam App Id 1968040

7. Outpost Defender 2-Beta

The Space-Outpost is under assault! You must defend it. Fight off infinite waves of alien invaders. Survive as long as possible. A retro/arcade pixel-art outbreak challenge to set the highest score! Single-player and Local Co-Op enabled.

Outpost Defender 2-Beta banner

Outpost Defender 2-Beta has achieved a Player Score of 78, placing it in the #7 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 15 reviews on Steam. This breaks down to a total of 15 positive reviews and 0 negative reviews — making it "Positive" on Steam.

It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.

Release Date 5/10/2022
Developer FluffyPants Games
Publisher FluffyPants Games
Steam App Id 1980520

8. Doomsday Dispute

Doomsday Dispute introduces a post-apocalypse world where you need to survive and find other survivors to start a new civilization.

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Doomsday Dispute has achieved a Player Score of 66, placing it in the #8 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 116 reviews on Steam. This breaks down to a total of 83 positive reviews and 33 negative reviews — making it "Mostly Positive" on Steam.

It can be played and ran on Windows systems. At the moment, it is not possible to play or run Doomsday Dispute on the Steam Deck.

Release Date 11/17/2021
Developer Doomsday Dispute
Publisher Doomsday Dispute
Steam App Id 1792710

9. Final Redoubt: Zombie Apocalypse

Survive the onslaught, manage your ammo, and endure in Final Redoubt, a relentless survival shooter where every bullet, every swing, and every decision counts!

Final Redoubt: Zombie Apocalypse banner

Final Redoubt: Zombie Apocalypse has achieved a Player Score of 60, placing it in the #9 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 7 reviews on Steam. This breaks down to a total of 5 positive reviews and 2 negative reviews — making it "7 user reviews" on Steam.

It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.

Release Date 1/28/2025
Developers
Publisher Jonathan T Freeman
Steam App Id 3443680

10. Collapsed

Challenge your mind with a 3D physics-based puzzle game. Take control of a cannon and use your limited supply of cannonballs to bring each level crashing to the ground. Using gravity, momentum, and logic, plan how to knock down each structure and leave nothing standing after the collapse!

Collapsed banner

Collapsed has achieved a Player Score of 67, placing it in the #10 spot for the best free Outbreak Sim games. Its score was calculated by analyzing a total of 26 reviews on Steam. This breaks down to a total of 20 positive reviews and 6 negative reviews — making it "Mostly Positive" on Steam.

It can be played and ran on Windows systems. At the moment, there is no confirmed information regarding Steam Deck support for this game.

Release Date 8/9/2022
Franchise YuzuGames
Developers
Publishers
Steam App Id 1949850

More Free Outbreak Sim Games

Explore even more rankings for the 20 best free Outbreak Sim games available on Steam.

Soures & References

Steambase has best-in-class data powered directly by Steam, our data partners, and in-house experts. Player counts and rankings are enriched, analyzed, and updated in real-time to ensure we surface the most up-to-date insights. Learn more about the Steambase approach to data collection and our review methodology.

  • Valve Corporation. (2025, July 29). Steam Store. Steam Store.
  • Valve Corporation. (2025, July 29). State of Survival on Steam. Steam Store.
  • Valve Corporation. (2025, August 18). Post-Apo Builder: Prologue on Steam. Steam Store.
  • Valve Corporation. (2025, June 14). 防疫英雄 on Steam. Steam Store.
  • Valve Corporation. (2025, August 16). Plane Accident: Prologue on Steam. Steam Store.
  • Valve Corporation. (2025, September 2). Zombie Siege City on Steam. Steam Store.
  • Valve Corporation. (2025, June 10). Life on the Edge on Steam. Steam Store.
  • Valve Corporation. (2025, March 18). Outpost Defender 2-Beta on Steam. Steam Store.
  • Valve Corporation. (2024, September 20). Doomsday Dispute on Steam. Steam Store.
  • Valve Corporation. (2025, August 14). Final Redoubt: Zombie Apocalypse on Steam. Steam Store.
  • Valve Corporation. (2025, September 5). Collapsed on Steam. Steam Store.

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