Videogames are a unique medium of entertainment for several reasons. The first and most obvious reason for this is the interactivity that comes with video games, which just cannot be matched by movies, television, books, or comic books. When other forms of media take inspiration from established pieces, one can often see the parallels between the two. Simply put, it is much harder to create a unique piece of media that was inspired by an existing thing outside of the video game world.
There are a good handful of games out there that began their existence as a mod for another game, one of the most successful and popular of which Team Fortress by Valve.
10 Team Fortress Classic Was Originally A Mod To Quake
The original Team Fortress game began its existence as a mod to the Id Software's pioneering shooter, Quake. Originally, Team Fortress was developed by TF Software Ltd., and they already had Team Fortress 2 in the works when they were hired by Valve to make a version of Team Fortress that served as a Half-Life mod.
In 2000, Team Fortress was released as a standalone game with the Half-Life 1.1 update and already included networking code for Team Fortress 2, which was released in 2007.
9 Counter-Strike Is The Hit FPS Spawned From Half-Life
Counter-Strike is another mod-based game that Valve was heavily involved in. However, Counter-Strike began as a mod for Half-Life created by Gooseman Le and Jess Cliffe. They were later hired by Valve, and Counter-Strike was made into a proper game.
Since then, Counter-Strike: Global Offensive has been released and has become a competitive FPS darling.
8 The Stanley Parable Sprouted From Half-Life 2
The Stanley Parable's origins lie with Half-Life 2, and it takes a far slower and more pensive approach to gameplay than Team Fortress or Counter-Strike. It is a metatextual ponderance on the nature of choice in video games and became a critically beloved hit.
This one was originally made by Davey Wreden and William Pugh, originally released as a Half-Life 2 mod in 2011. The two later released a standalone version of the game in 2013.
7 DayZ, The Zombie-Flavored Spawn Of ARMA 2
DayZ is the hardcore survival simulator set in a world overrun by zombies. However, other players are just as, if not more, hazardous to the survivor's health than the zombies themselves. This game began as a mod to the survival sim, ARMA 2 by Bohemia Interactive.
The DayZ mod was released in 2012 and went into early access soon after with the intent of becoming a standalone game. DayZ was completed as a full game in 2018 with console ports in 2019.
6 DOTA 2, The Valve Game That Originated With Warcraft III
DOTA, or Defense of the Ancients, began its journey as a mod to the real-time strategy, Warcraft III: Reign of Chaos. It helped spawn the MOBA, or multiplayer online battle arena, genre. The mod was created using the World Editor feature of Warcraft III and maintained by a development team headed by IceFrog.
DOTA was incredibly popular and was even featured in BlizzCon tournaments. However, Valve later obtained the rights to DOTA and released DOTA 2 in 2013.
5 Heroes Of The Storm, The Unlikely Child Of StarCraft II: Wings Of Liberty
Heroes of the Storm began as "Blizzard DOTA" and was showcased at BlizzCon 2010 as a map for StarCraft II: Wings of Liberty. It was intended to show how moddable StarCraft II was, but "Blizzard DOTA" eventually took on a life of its own and entered alpha testing in 2014. By then it had changed from "Blizzard DOTA" to "Blizzard All-Stars" and, finally, Heroes of the Storm.
The full game was released in 2015. It had some competitive and casual hype around it for a time, but Heroes of the Storm entered a state of decline in 2018 and hasn't recovered since.
4 PlayerUnknown's Battlegrounds Was Created From ARMA 3
The smash-hit battle royale game known as PlayerUnknown's Battlegrounds or PUBG began its existence as a mod to ARMA 3. The game was headed by Brendan Greene in its earliest stages, and it took the survival concept of ARMA 3 and gave a distinct multiplayer objective-based game mode to ARMA.
The game was released as a standalone title with the help of Bluehole Entertainment in 2017, with the company dedicating an entire studio now known as the PUBG Corporation to the title.
3 Killing Floor Is The Bloody Offspring Of Unreal Tournament 2004.
The multiplayer horror-based survival game known as Killing Floor began its life as a mod to Unreal Tournament 2004, a game that is largely used to show the power of the Unreal Engine and encourages modders to see what they can make with the platform.
Alex Quick was the lead developer on the Killing Floor mod, which was initially released in 2005. He was later approached by Tripwire Interactive, and the two released a standalone Killing Floor in 2009. Killing Floor would receive a sequel in 2016.
2 Dear Esther, The Pensive Walking Simulator Born Of Half-Life 2
Dear Esther began its won journey as a Source Engine mod to Half-Life 2 developed by the Chinese Room. At this point, the development studio was still part of the University of Portsmouth. The development was led by Dan Pinchbeck.
The original Dear Esther was released in 2008 with a standalone version released in 2012. The Chinese Room would go onto make Amnesia: A Machine for Pigs in 2013, Everybody's Gone to the Rapture in 2015, and a redux of Dear Esther in 2017.
1 X-Men: The Ravages Of Apocalypse, a Marvel-Backed Mod To Quake
X-Men: The Ravages of Apocalypse is a total conversion mod to Id's Quake released in 1997 by Zero Gravity Entertainment. Marvel Comics even gave this mod their blessing. The gameplay involved the player character fighting off cyborg clones of popular X-Men characters, presumably transformed by the titular villain, Apocalypse.
The game required Quake to play, and it wasn't well-loved by audiences. However, it was finally released as a free standalone game in 2006.