From Mods To Major Titles
A mod is often just a way to add a little extra to a game. But sometimes, that extra is all it takes to spark something completely new. Many game projects started as side gigs, created by fans who loved the original game, but over time, they became full-fledged titles in their own right. It’s proof that creativity and passion can lead to some pretty wild, unexpected outcomes. Here, we’ll show you 20 mods that finally found their footing and became their own thing.
1. Counter-Strike
Starting as a Half-Life mod in 1999, Counter-Strike combined tense tactics with bomb-defusal and hostage rescue. What started as a fan project quickly became a powerhouse. In 2020, Valve launched it as a standalone title.
History of - Half-Life & Counter Strike (1998-2007) by blablue123
2. PUBG
An ARMA 2 mod cracked open a whole new genre. Born as the Battle Royale mod, this Brendan PlayerUnknown Greene brainchild morphed into PUBG in 2017. Suddenly, everyone was chased by the blue zone and scrambling for frying pans.
ARMA 3: Battle Royale Mod — First Impressions — Part 1 — Tower Troubles! by PsiSyn
3. Ricochet
Not every standalone mod becomes a household name. Ricochet started as a quirky experiment built on the original Half-Life engine and somehow convinced Valve to give it a full release in 2002. With neon platforms and disc-slinging chaos, it quickly earned a cult following.
Do People Still Play Ricochet? by TheWarOwl
4. Dota
Dota started as a custom mod for Warcraft III, originally titled Defense of the Ancients. In 2013, Valve reimagined it into Dota 2 and took the game to new heights. Its monumental impact is clear, with The International's prize pool exceeding $40 million.
Dota 2 - Games of 2013 - Eurogamer by Eurogamer
5. Zombie Panic
The game crawled out of modding for Half-Life 2 in 2007 and forced humans to band together—until they turned into zombie foes themselves. With permadeath, proximity-focused voice chat, barricading action, and full-on panic mode, it's a frantic fight for survival.
Zombie Panic! Source 3.2 Pro Gameplay Cinema by Moto Runner
6. Killing Floor
If you dug Unreal Tournament's fast-paced blasting, Killing Floor's 2009 debut as a standalone co-op shooter injected it with buckets of gore and an undead apocalypse twist. Starting as a mod in 2004, it gained fame for its slow-motion "Zed Time".
Zed Time Event In Real Time by Theta Zero
7. Natural Selection
In 2002, this game emerged as a Half-Life mod that merged RTS and FPS mechanics and gave players the chance to control alien lifeforms against humans in an epic struggle for dominance. Its success led to Natural Selection 2, released as a standalone game in 2012.
Natural Selection 2: Darwinism for Dummies by Criken2
8. Red Orchestra
Before launching as Ostfront 41-45 in 2006, Red Orchestra took root as a mod for Unreal Tournament. It's not about run-and-gun—this shooter went all-in on realism, with bullet drop, iron sights, and meticulously accurate WWII battles. History nerds and sharpshooters alike found a home.
Red Orchestra: Ostfront 41–45 Multiplayer in 2025 by Classic PC Games
9. The Stanley Parable
With a snarky narrator gleefully breaking the fourth wall, this one began as a mod for Half-Life 2 before evolving into a standalone game built on the Portal 2 engine branch. Expansions like Ultra Deluxe in 2022 only deepened its playful critique of choice in video games.
The Stanley Parable: Ultra Deluxe | FULL GAME by Markiplier
10. Chivalry
Born from the Age of Chivalry mod for Half-Life 2, Chivalry: Medieval Warfare took the world by storm in 2012 with its brutal melee combat. Its success sparked Chivalry 2, adding mounted combat and solidifying the franchise as a fan favorite.
What Went Wrong? - Chivalry Medieval Warfare, Mordhau, Mirage and More by WickedWiz
11. Sven Co-op
Teamwork was the name of the game when Sven Co-op first brought co-op to Half-Life, but after its 2016 standalone launch, it took things further. It served up epic campaigns, ongoing Half-Life map support, and community-made levels to keep the co-op fun alive and buzzing today.
How to destroy the Ospery Helicopter with Revive Boost | Sven Co-op by Benjamin
12. Fortress Forever
Instead of letting Team Fortress Classic fade into oblivion, a gang of fans took matters into their own hands, modding Half-Life 2 to revive that beloved formula. Their dedication paid off when Fortress Forever launched standalone in 2007.
Team Fortress Classic Gameplay (PC HD) [1080p60FPS] by Throneful
13. No More Room In Hell
A little darker and grimmer, this one began as a Source mod for Half-Life 2 with a chilling zombie survival twist. When it was released as a standalone game in 2011, the game stripped away the HUD and threw players into chaotic survival moments where cooperation was key.
I Tried To Beat Every Map In No More Room In Hell Solo by ProtoShard
14. Estranged
What starts as just another Half-Life 2 mod can turn into something beautifully atmospheric—case in point, Estranged. Solo dev Alan Edwardes poured spooky island vibes and mysterious storytelling into this project, and by 2014, he'd turned it into a standalone treat on Steam.
Estranged: Act 1 - Full Walkthrough/Gameplay [No Commentary] by tombevil
15. Black Mesa
With Half-Life love running deep, a community of fans decided to go all in and remake the iconic original as a mod called Black Mesa. Fifteen years later, it finally burst onto Steam as a commercial title in 2020.
16. DayZ
DayZ originated as a modification for ARMA 2 and later became a standalone game that pioneered emergent narrative gameplay. In addition, players weren't only surviving against zombies but against other players, too, which added a whole new level of tension and excitement.
Spin to Win in DayZ!!! by NeonBlackNinja
17. The Forgotten City
Originally a mod for Skyrim, The Forgotten City quickly developed into something bigger. Fast forward to 2021, and it evolved into a standalone time-travel adventure—and won the Australian Game of the Year award along the way.
The Forgotten City Review - The Best Video Game Surprise Of The Year? Time Loop Game by Andy's Take
18. Garry’s Mod
Garry's Mod launched as a mod for Half-Life 2 and then became a standalone title in 2006, immediately taking off with gamers. Known for its chaotic physics and player-driven creativity, the game didn't have any predefined objectives—it was all about what players could make of it.
I miss Garry's Mod... by Kelski
19. Dear Esther
Forget guns and explosions, Dear Esther took a more subtle route. Emerging from a Half-Life 2 mod in 2012, it focused on poetic storytelling through a windswept island that sparked a new wave of narrative-focused games like Gone Home and Firewatch.
Great Poetic Story | DEAR ESTHER (Full Playthrough) by M3atY
20. Insurgency
Insurgency started as a tactical mod for Half-Life 2 in 2007. By 2014, it nailed a tense solo release with no HUD, hyper-real gunplay, and teamwork-or-die rounds. With its no-nonsense gameplay and strategic depth, Insurgency pulled in a direct sequel with Insurgency: Sandstorm.
