Free Moddable Games on Steam
Steam currently has 1,917 Moddable 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 Moddable game rankings were last updated on 12/10/2025.
Looking for more? Explore other lists such as:
- Best moddable games on Steam
- Best moddable Steam Deck games
- Best moddable Steam games for Mac OS
- Best moddable Linux games on Steam
- Free Steam games
- Most played Steam games
- Best rated Steam games
1. Counter-Strike 2
For over two decades, Counter-Strike has offered an elite competitive experience, one shaped by millions of players from across the globe. And now the next chapter in the CS story is about to begin. This is Counter-Strike 2.
Counter-Strike 2 holds the #1 spot for "best free Moddable game on Steam" with a Player Score of 86. Its score was calculated by analyzing a total of 9,212,305 reviews on Steam. This breaks down to a total of 7,954,468 positive reviews and 1,257,837 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on both Windows and Linux systems. At the moment, it is possible to play Counter-Strike 2 on the Steam Deck (though some functionality may be limited).
2. tModLoader
Dig, Fight, and Build your way through the world of player-created mods on Terraria with tModLoader - this DLC makes modding Terraria a reality!
tModLoader has achieved a Player Score of 96, placing it in the #2 spot for the best free Moddable games. Its score was calculated by analyzing a total of 343,438 reviews on Steam. This breaks down to a total of 333,586 positive reviews and 9,852 negative reviews — making it "Overwhelmingly Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play tModLoader on the Steam Deck (though some functionality may be limited).
3. Blender
Blender is the free and open source 3D creation suite. Free to use for everyone, for any purpose.
Blender has achieved a Player Score of 95, placing it in the #3 spot for the best free Moddable games. Its score was calculated by analyzing a total of 80,597 reviews on Steam. This breaks down to a total of 77,535 positive reviews and 3,062 negative reviews — making it "Overwhelmingly Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is not possible to play or run Blender on the Steam Deck.
| Release Date | 4/24/2015 |
| Developer | Blender Foundation |
| Publisher | Blender Foundation |
| Steam App Id | 365670 |
4. Age of Empires III: Definitive Edition
Age of Empires III: Definitive Edition offers players a trial of this historical single & multiplayer RTS experience. *Note: To unlock all features of the game please see the “Base Game” product.
Age of Empires III: Definitive Edition has achieved a Player Score of 84, placing it in the #4 spot for the best free Moddable games. Its score was calculated by analyzing a total of 51,229 reviews on Steam. This breaks down to a total of 43,589 positive reviews and 7,640 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows systems. At the moment, it is possible to play Age of Empires III: Definitive Edition on the Steam Deck (though some functionality may be limited).
| Release Date | 10/15/2020 |
| Franchise | Age of Empires Franchise |
| Developers | |
| Publisher | Xbox Game Studios |
| Steam App Id | 933110 |
5. VPet-Simulator
Feeling like the computer desktop is too dull? Need something cute to heal oneself? Come and try this new completely free and open source V-Pet simulator. A cute and adorable pet that supports various feeding interactions to accompany you in game learning is definitely your best choice!
VPet-Simulator has achieved a Player Score of 96, placing it in the #5 spot for the best free Moddable games. Its score was calculated by analyzing a total of 49,487 reviews on Steam. This breaks down to a total of 48,650 positive reviews and 837 negative reviews — making it "Overwhelmingly Positive" on Steam.
It can be played and ran on Windows systems. At the moment, it is not possible to play or run VPet-Simulator on the Steam Deck.
6. Crusader Kings II
Explore one of the defining periods in world history in an experience crafted by the masters of Grand Strategy.
Crusader Kings II has achieved a Player Score of 89, placing it in the #6 spot for the best free Moddable games. Its score was calculated by analyzing a total of 73,072 reviews on Steam. This breaks down to a total of 66,170 positive reviews and 6,902 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play Crusader Kings II on the Steam Deck (though some functionality may be limited).
| Release Date | 2/14/2012 |
| Franchise | Crusader Kings Official |
| Developer | Paradox Development Studio |
| Publisher | Paradox Interactive |
| Steam App Id | 203770 |
7. Source Filmmaker
The Source Filmmaker (SFM) is the movie-making tool built and used by us here at Valve to make movies inside the Source game engine. Because the SFM uses the same assets as the game, anything that exists in the game can be used in the movie, and vice versa.
Source Filmmaker has achieved a Player Score of 91, placing it in the #7 spot for the best free Moddable games. Its score was calculated by analyzing a total of 42,070 reviews on Steam. This breaks down to a total of 39,093 positive reviews and 2,977 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows systems. At the moment, it is not possible to play or run Source Filmmaker on the Steam Deck.
8. DDNet
Want to play the hardest cooperative 2D platformer ever? Want to finish no map ever? Want to be in pain for hours and cry, getting nothing in return? Come play DDNet with a large community of other sufferers!
DDNet has achieved a Player Score of 87, placing it in the #8 spot for the best free Moddable games. Its score was calculated by analyzing a total of 41,767 reviews on Steam. This breaks down to a total of 37,026 positive reviews and 4,741 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play DDNet on the Steam Deck (though some functionality may be limited).
| Release Date | 8/17/2020 |
| Developer | DDNet Team |
| Publisher | DDNet Team |
| Steam App Id | 412220 |
9. OpenTTD
OpenTTD is a business simulation game in which players earn money by transporting passengers and cargo via road, rail, water, and air. It is an open-source remake and expansion of the 1995 Chris Sawyer video game Transport Tycoon Deluxe.
OpenTTD has achieved a Player Score of 94, placing it in the #9 spot for the best free Moddable games. Its score was calculated by analyzing a total of 15,400 reviews on Steam. This breaks down to a total of 14,816 positive reviews and 584 negative reviews — making it "Overwhelmingly Positive" on Steam.
It can be played and ran on Windows, Mac, and Linux systems. At the moment, it is possible to play OpenTTD on the Steam Deck (though some functionality may be limited).
10. Sven Co-op
Sven Co-op is a co-operative game originally based around Valve Software's Half-Life. In this game players must work together against computer controlled enemies and solve puzzles as a team.
Sven Co-op has achieved a Player Score of 92, placing it in the #10 spot for the best free Moddable games. Its score was calculated by analyzing a total of 31,786 reviews on Steam. This breaks down to a total of 29,754 positive reviews and 2,032 negative reviews — making it "Very Positive" on Steam.
It can be played and ran on both Windows and Linux systems. At the moment, it is possible to play Sven Co-op on the Steam Deck (though some functionality may be limited).
| Release Date | 1/22/2016 |
| Developer | Sven Co-op team |
| Publisher | Sven Co-op team |
| Steam App Id | 225840 |
More Free Moddable Games
Explore even more rankings for the 100 best free Moddable games available on Steam.
| Image | Name | Actions | ||||
|---|---|---|---|---|---|---|
| 830,475 | 8/21/2012 | 86 | Free | Steam Charts | |
| 23,521 | 5/16/2020 | 96 | Free | Steam Charts | |
| 8,717 | 4/24/2015 | 95 | Free | Steam Charts | |
| 4,170 | 10/15/2020 | 84 | Free | Steam Charts | |
| 2,516 | 8/13/2023 | 96 | Free | Steam Charts | |
| 1,690 | 2/14/2012 | 89 | Free | Steam Charts | |
| 1,060 | 7/10/2012 | 91 | Free | Steam Charts | |
| 929 | 8/17/2020 | 87 | Free | Steam Charts | |
| 675 | 4/1/2021 | 94 | Free | Steam Charts | |
| 354 | 1/22/2016 | 92 | Free | Steam Charts | |
 | 341 | 6/25/2021 | 91 | Free | Steam Charts | |
 | 333 | 7/1/2014 | 66 | Free | Steam Charts | |
 | 286 | 4/20/2017 | 93 | Free | Steam Charts | |
 | 256 | 11/17/2021 | 68 | Free | Steam Charts | |
 | 242 | 4/30/2015 | 76 | Free | Steam Charts | |
 | 233 | 4/14/2023 | 93 | Free | Steam Charts | |
 | 222 | 5/6/2021 | 88 | Free | Steam Charts | |
 | 204 | 2/15/2023 | 76 | Free | Steam Charts | |
 | 203 | 1/6/2024 | 94 | Free | Steam Charts | |
 | 137 | 8/20/2022 | 96 | 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, December 10). Steam Store. Steam Store.
- Valve Corporation. (2025, December 10). Counter-Strike 2 on Steam. Steam Store.
- Valve Corporation. (2025, December 12). tModLoader on Steam. Steam Store.
- Valve Corporation. (2025, December 10). Blender on Steam. Steam Store.
- Valve Corporation. (2025, December 12). Age of Empires III: Definitive Edition on Steam. Steam Store.
- Valve Corporation. (2025, December 1). VPet-Simulator on Steam. Steam Store.
- Valve Corporation. (2025, November 26). Crusader Kings II on Steam. Steam Store.
- Valve Corporation. (2025, December 6). Source Filmmaker on Steam. Steam Store.
- Valve Corporation. (2025, December 14). DDNet on Steam. Steam Store.
- Valve Corporation. (2025, December 14). OpenTTD on Steam. Steam Store.
- Valve Corporation. (2025, November 16). Sven Co-op on Steam. Steam Store.