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.
Looking for more? Explore other lists such as:
- Best outbreak sim games on Steam
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1. State of Survival
Survive the Zombies War in this RPG game of Apocalypse and Survival
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
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 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.
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 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 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 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.
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 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.
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 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 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.
More Free Outbreak Sim Games
Explore even more rankings for the 20 best free Outbreak Sim games available on Steam.
| Image | Name | Actions | ||||
|---|---|---|---|---|---|---|
| 110 | 8/2/2023 | 56 | Free | Steam Charts | |
| 2 | 8/2/2023 | 66 | Free | Steam Charts | |
| 1 | 6/23/2022 | 60 | Free | Steam Charts | |
| 1 | 1/18/2024 | 63 | Free | Steam Charts | |
| 1 | 11/2/2024 | 61 | Free | Steam Charts | |
| 1 | 6/17/2022 | 80 | Free | Steam Charts | |
| 1 | 5/10/2022 | 78 | Free | Steam Charts | |
| 1 | 11/17/2021 | 66 | Free | Steam Charts | |
| 1 | 1/28/2025 | 60 | Free | Steam Charts | |
| 1 | 8/9/2022 | 67 | Free | Steam Charts | |
 | 1 | 3/10/2023 | 37 | Free | Steam Charts | |
 | 1 | 10/19/2023 | 88 | Free | Steam Charts | |
 | 1 | 4/6/2023 | 53 | Free | Steam Charts | |
 | 1 | 2/8/2021 | 79 | Free | Steam Charts | |
 | 1 | 1/8/2024 | 76 | Free | Steam Charts | |
 | 1 | 3/7/2024 | 80 | Free | Steam Charts | |
 | 1 | 1/27/2023 | 62 | Free | Steam Charts | |
 | 1 | 12/31/2024 | 60 | Free | Steam Charts | |
 | 1 | 3/17/2021 | 72 | Free | Steam Charts | |
 | 1 | 5/15/2025 | 60 | Free | Steam Charts |
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.