Video game modding

Spacewar! (1962) and early endeavors '' on a PDP-1 A specific date of origin for video game modding has not been agreed upon by historians, partly due to discussion over what constitutes a mod and partly because of insufficient historical documentation. Widely considered one of the first computer games, the 1962 game Spacewar! was distributed freely as testing software for the PDP-1, an early computer. and software experimentation, supported by the programming culture On university campuses where the computer was installed, programmers continued to experiment with the game by modifying it heavily, In this way, Spacewar! was not only the first video game, but also the first video game to be modded.Other early video games also released as iterations of collaborative improvements. Colossal Cave Adventure, a text adventure game developed by Will Crowther and released in 1976, was greatly expanded upon by Stanford graduate Don Woods. While modders created amateur game editing tools out of necessity, they were often buggy, inefficient, and incomplete, ultimately necessitating good programming skills for mod development. New assets were processed through multiple software packages in order to be modded into the game engine. With Wolfenstein 3D, players had to erase game data to replace it; this destructiveness concerned Carmack and Romero. When developing Doom, Carmack purposely separated the game engine files from other assets, including level architecture, graphics, and audio, Valve used WorldCraft, a fan-produced tool for Quake, to design Half-Life. a game mode created by John Romero for Doom. The multiplayer mods Day of Defeat and Counter-Strike'' became popular, and eventually Valve acquired them, giving them an official release. With the increase in popularity of the modding scene, video game companies began to capitalize on the appeal of creating user-generated content. By the mid-1990s, PC games were commonly bundled with modding tools, external software which allows users to create mods for their paired games. Steam, a video game digital distribution service created by Valve Corporation, was specifically designed for the proliferation of successful, stand-alone mods. The platform offered a US$995 licensing fee plus royalty for modders to distribute their games. Steam included a retail-version of Day of Defeat, originally a total conversion mod for Valve's Half-Life whose rights were purchased by the company. Gabe Newell, the founder of Valve, noted that his perception of video games shifted from viewing them as entertainment to embracing them as "productivity platforms". Since then, the client has become one of the largest online marketplaces for games. The platform introduced full support for finding and playing mods for Valve's Team Fortress 2, The Steam Workshop, introduced to the platform in 2012, allows players to mod Steam-hosted games directly within the interface. Paid mods on Steam In April 2015, Valve introduced paid mods to the Steam Workshop as an update to the free system already in place. Mod authors received a cut of the profits from mods sold through Steam, with the percentage being determined individually by game developers. The first game to utilize the feature was Bethesda's The Elder Scrolls V: Skyrim, with mod authors receiving 25 percent of profit from their sales while the remainder was split between Valve and Bethesda. Gabe Newell, the head of Valve, expressed that paid mods would "increase the investment in quality modding", while not infringing on the need for freely distributed mods. The Workshop update resulted in backlash from the modding community, with complaints including having to pay for previously free mods; Paid mod authors were also the target of backlash, with some receiving death threats and harassing comments. A Change.org petition was launched to remove the feature, garnering over 130,000 signatures. The removal itself was criticized by mod developers. ==Development==

Developing a video game mod requires a range of technical and social skills, such as programming, 3D modeling, sound design, art, and project management. Modders represent a wide spectrum of individuals with varying degrees of experience, skill sets, motivations, Using community feedback and bug reports, mod authors release a median of two updates to their mods, often back-to-back, according to an empirical study of mods hosted on the website Nexus Mods. A majority of mods on the platform are released over 300 days after a game's release, indicating that mod developers are either long-time players or have developed a renewed interest in a game. Video game consoles remain largely proprietary and are equipped with strict security measures and a closed infrastructure that prohibits modding. In some cases, the console versions of games, such as Fallout 4, allow modding through in-game menus, subject to approval. and ''The Bard's Tale Construction Set, released in 1991, which allow users to create games using the engines of their predecessors. In 1983, Lode Runner was released with a level editor in which users could make and save levels to share with other players on the same computer. It is considered one of the first games to support user mods. The provision of tools is seen as the most practical way that a company can signal to fans that its game is available to mod. As of 2020, 9 out of 10 of the most modded games on Nexus Mods have an official modding tool from the game developer. These tools are often similar to the ones used by the game developer. The advertising campaign for Neverwinter Nights focused on the included Aurora toolset.'' Bethesda Game Studios offers the Creation Kit, a program containing user-tailored modding tools used to create mods for their games, including The Elder Scrolls V: Skyrim''. Modders also create and use open-source software tools for creating mods. With games where modding is unsanctioned, these user-developed tools are the only resources available to develop mods. Examples include tools written to view 3D-geometry and programs used to import this data into 3D-applications, such as Maya or Autodesk 3ds Max. Because game developers encrypt their game's files, unsanctioned modding requires reverse engineering the structure of the game through extracting and decrypting files. This process is facilitated through the sharing of game files on modding forums, such as the XeNTaX community which produced modded versions of Metal Gear Solid V: The Phantom Pain starting in 2015. particularly for assets such as textures and voice acting, which can present a barrier to entry for amateur mod teams. Voice actors have raised ethical concerns over their voices being cloned without their consent, and they have denounced pornographic mods that use their cloned voices. Websites for hosting and sharing mods are widely used by the modding community. Mod DB was founded in 2002, with over 300 million mod downloads as of 2025. Since its inception in 2001, Nexus Mods has become one of the largest modding websites; as of 2024, the website has over 47 million members and hosts a total of 539,682 mod files, developed by 128,361 mod authors. The website accrued a lifetime total of 10 billion mod downloads for 2,683 games the same year. Other websites are dedicated to the modding scenes of specific games. Large mod teams often host their own websites to showcase the development of their mods. These websites feature detailed database and advanced search functionality that allow users to easily find mods for their games, becoming social centers for modders and their shared knowledge. Free content delivery tools, known as "mod managers", are available to streamline the mod installation process and aid players who are less technically literate. These tools manage downloads, updates, and mod installation. Steam offers the Steam Workshop within the game launcher itself, allowing a users to share mods for simplified download and installation in supported games. Game developers also create official mod managers either alongside their games, such as the Paradox Launcher for games created by Paradox Interactive, or within the games themselves, such as in ''Baldur's Gate 3''. Game support A game that allows modding is said to be moddable, and the extent to which a game can be modded is called its moddability. In general, moddable games will define gameplay variables in text or other non-proprietary format files and have graphics of a standard format, such as bitmaps. Developers can also foster mod-friendliness by making source files more accessible, such as Doom separating its art assets from the main program. Some mods increase moddability by adding scripting support or externalizing underlying code. In 2025, mod authors released a script extender for The Elder Scrolls IV: Oblivion Remastered, which has no official mod support, in less than six hours after the game's release. Video game developer reception of player contribution in creating new material for games and mod-communities is varied. Some software companies openly accept and even encourage such communities, with moddability being a contributing factor to the some games' success. Others have chosen to enclose their games in heavily policed copyright or Intellectual Property regimes (IPR) and shut down sites infringing on their ownership of a game. == Motivations ==

While a few modders have a pre-existing desire to create modifications for the games they play, most modders start modding more or less accidentally, utilizing their prior interests like drawing, architecture, and programming. Their motivations for creating mods vary and often changes over time. Motivations can range from a general interest in their favorite game and the desire to modify it, to personal interests like artistic self-expression and technical challenges, as well as wanting to participate in a modding community. While a modder may be motivated by a combination of factors, there is typically one primary motivator. Modding can serve as a pathway to entering the video game industry, with mod makers often featuring mod projects in their portfolios when applying for jobs in the industry. Modding tools provide the opportunity to acquire or refine information technology expertise for novices with prospects of eventually working in the games industry or related fields. For players who identify as LGBTQ, motivations for modding can stem from a lack of representation in a game and its modding community. Options for homosexual romance and character genders are made available through "queer mods". Examples include the "Equal Love Mod" for Dragon Age: Origins and a similar mod for Mass Effect, which enable romance with characters normally unavailable for their protagonist's gender. Researcher Evan Lauteria theorized that queer mods can be an act of resistance against the limitations on sexual normativity enacted by the game, such as compulsory heterosexuality. Likewise, programmers may be motivated by the innate challenge of hacking a game as a "complex code-based system", often creating mod tools for other mod makers. Sense of community Modder communities are made up of people with diverse interests, from military and social history to technological expertise. Combined, these skills add to the richness of mods. Modding has been described as a part of remix culture and as a successor to the hacker culture that produced the first video games. It has been correlated with the introduction of Web 2.0, which encourages collaboration and participation via the Internet through the production and alteration of user-generated content. The sense of community, feedback, recognition, and sources of inspiration fostered through online, collaborative discussions are various motivators that influence the development and sharing of mods. This sense of community can transcend alienation and help challenge the stigma that gaming is "antisocial, isolating, or creatively stifling". == Impact ==

The game industry's support of modding has been crucial to the rise of the modding phenomenon. Beginning in 1999, the company held an annual mod expo showcasing new games built using GoldSrc, the Half-Life engine, including Gunman Chronicles and Counter Strike which both later released as stand-alone titles. In early 2012, the DayZ mod for ARMA 2 was released, causing a massive increase in sales for the three-year-old game and putting it in the top spot for online game sales for a number of months. As of 2020, the top three games by esports prize pools all originated as mods: Dota 2 (US$174 million), Counter-Strike: Global Offensive (US$69M), and League of Legends (US$64M). The developer of the Civilization series, Firaxis has included user mods, "Double Your Pleasure", throughout expansion packs for the franchise. Series developer Sid Meier, who had previously opposed mods in the franchise, later said that "the strength of the modding community is [...] the very reason the series survived". Valve hired Defense of the Ancients lead designer IceFrog for the development of the stand-alone, official sequel. The introduction of real-life brands through video game mods can result in positive brand reception, increased further through discussions on modding forums and video hosting websites. == Issues ==

Legal status Copyright law relating to video games and mods is an evolving legal issue. Uncertainty revolves around which party is legally the copyright owner of the mods—the company that produced the game, the creators of the individual mods, or the player that installed the mods. Under current law, mods are viewed as derivative works, as they are based upon or incorporate part of the original game In US copyright law, different statutes cover various aspects of video games, such as graphics, audio, and source code. Most pertinent is the Copyright Act of 1976 (), which protects "pictorial, graphic, and sculptural works", "sound recordings", and "literary works", among others. Despite the lack of legal protection, modding continues to thrive due to encouragement from video game developers, who make moddable games. An example is Electronic Arts (EA), who qualifies modding for their games, such as The Sims 4, according to their EULA from 2022: "When you contribute UGC, you grant to EA […] sublicensable license to use, host, store, reproduce, modify, create derivative works, publicly perform, publicly display or otherwise transmit and communicate the UGC". Additionally, companies may take legal action against mods for multiplayer games which could impact fairness. Another concern is the use of copyrighted material owned by another company, such as a mod for Quake themed around Alien vs. Predator which was legally contested by 20th Century Fox. Some modders regard the use of copyrighted material in mods to be part of a "moral economy", often settling on a system of shared ownership, where mods and code are freely shared with the common good in mind. Modding can be compared to the open-source-software movement and open-source video game development. In 2006, Second Life generated interest from its focus of user-generated content (mods) and how intellectual property rights to this content remained with the creator. Second Life players are able to sell these items in an in-game market. Literature on user-generated content in video games in the context of UK and European copyright law is limited. Scholarship mostly concerns the liabilities of intermediaries who provide this content rather than creators themselves. In 2015, members from GTAForums, a Grand Theft Auto fan site, reported instances of malware being circulated through mods written for Grand Theft Auto V. Two of the mods in question, "Angry Planes" and "No Clip", came with malicious code for loading a remote access tool and a keylogger for stealing Facebook and Steam account credentials. Controversial mods Mods can alter games to reveal nudity and explicit content or introduce it via modded graphics. After the "Hot Coffee" mod incident, the games industry called for better control of explicit mods. Kotaku noted that the later-removed mods tweaked the game's preexisting nude character model, simply allowing it to appear throughout the game. Bethesda Softworks does not allow mods with nudity to be uploaded to its platforms. Nexus Mods allows for mods with nudity as long as nudity is not present in the preview image for the download page, such as Caliente's Beautiful Bodies Edition, which allows for body modification in Bethesda's Skyrim and Fallout 4 and has been downloaded at least 8.2 million times. Game developers and publishers retain the discretion to limit and remove political and discriminatory mods for their games. In 2016, Paradox Interactive took down a Steam Workshop mod for their game Stellaris which replaced non-white human characters with white ones, stating that they did not "wish to enable discriminatory practices". As of 2025, EA's mod policy stated that they held the right to "address any inappropriate Mods", including those with obscene or objectionable content. In the same year, the company submitted a copyright infringement notice to forums hosting a The Sims 4 mod which altered or removed representations of LGBTQ and Black people. Additionally, mod-hosting websites have removed potentially objectionable or divisive mods. Ahead of the 2020 United States presidential election, Nexus Mods updated their Terms of Service to state that content that promotes "conflict, division and mob harassment" would be removed. In 2025, the website removed a mod for Marvel Rivals which replaced the model for Captain America with one of Donald Trump, citing the updated policy. Additionally, the website has removed several mods that targeted LGBTQ themes, including a mod which removed pride flags from ''Marvel's Spider-Man; a mod which changed the gender of a non-player character (NPC) in a same-sex relationship in Baldur's Gate 3; and a mod which changed the "body type" option to male or female for The Elder Scrolls IV: Oblivion Remastered''. Paid mods While generally satisfied with working for free, Criticisms of the change came from Sims 4 creators and mod authors who sold mods through an early access model on crowdfunding websites and released completed mods for free. The policy was later updated to allow paid mods using the early access model while still prohibiting completed mods sold with an explicit paywall. In 2024, Nexus Mods clarified their policies regarding the hosting of paid mods, including disallowing mods that require other paid mods as a prerequisite as well as lite and demo versions of externally hosted paid mods, citing that paid modding is "in direct conflict" with their goal of making modding easy. with criticisms of the price, the harm on the community, and the practice of abandoning free mods in favor of pushing paid updated versions. The system was present in the 2024 release of Starfield, where it received similar negative reception. However, Creations has also been praised as a mutually beneficial platform that allows modders to work with game developers and have their work promoted in game. Arguments against paid mods have been diverse across mod users and developers. Some users denounce developers who sell mods as "sellouts", arguing that modding should be a "labor-of-love". Criticism has been drawn towards the price of cosmetic mods, with users pointing out that the sale of third-party assets used in many mods could be classified as copyright infringement. With Steam's introduction of paid mods in 2015, users were apprehensive about the centralization and surveillance of modding, as all submitted mods had to be approved by Steam. Other users mentioned that creators deserve to be compensated for their work and were open to paying for extensively elaborate mods. ==Types==

In the context of video games, the words "mod" and "modification" are not primarily academic terms and are sometimes used in conflicting ways to encompass and distinguish varieties of alterations to video games. Generally, as defined and used by players, mod makers, and gaming press, the definition of video game modding is the alteration or addition of content to an existing video game with user-generated content, particularly on PC. This understanding can significantly differ between game genres. As modding is an evolving concept, there is no exhaustive list of all types of mods nor agreement on what each type of mod encompasses. Defense of the Ancients, which was the first MOBA to have sponsored tournaments, and ''Garry's Mod, for which fans created thousands of game modes over its decade-long development. League of Legends and Dota 2 were both originally mods for Warcraft III: Reign of Chaos. and GTA 5 Redux'', which improves the original game's textures, adds a new weather system, and adjusts visual effects, the wanted system, weapons, and vehicle handling. Randomizer Randomizers are a type of user mod that keep the fundamental gameplay but randomize elements of the game to make it more of a challenge. Randomizers came out of the speedrunning community which had exhausted the challenge of racing through the game. Their popularity grew as randomizer playthroughs were popular with streaming media. Some games have offered official randomizer modes in the game itself, such as Cassette Beasts in 2023, or in downloadable content, including Bloodstained: Ritual of the Night in 2020, and Axiom Verge in 2021. Add-on An add-on or addon is a term which encompasses various levels of complexity, including mods, maps, skins, and other changes to game play. In the fourth quarter of 2005, Rockstar released a "clean" version of the game with the "Hot Coffee" scenes removed, and the rating of the game was reverted to Mature. In May 2006, a similar event occurred with The Elder Scrolls IV: Oblivion. In particular, these mods may include support for screen readers, color filters and graphical adjustments for colorblind players, modified audio cues, and pathfinding systems, among other features. Art mod An art mod is a mod that is created for artistic reasons or to provoke a reaction in the audience. Art mods are frequently associated with video game art. Modified games that retain their playability and are subject to more extensive mods (i.e. closer to total conversions) may also be classified as art games. One example is the Velvet-Strike mod for Counter Strike, in which the players spray paint anti-violence messages in multiplayer games as a form of performance art. In Robert Nideffer's Tomb Raider I and II patches, the unofficial Nude Raider patch of the late 1990s was alluded to and subverted by altering the main character's sexual orientation. The 1983 mod Castle Smurfenstein is a humorous subversion of Castle Wolfenstein which replaces the Nazi guards with Smurfs. After over a month, the creators revealed that the faked footage was created using a modded version of the game and released the mod to the public along with map-modding tools that were first of their kind for the game. Support continuation by mods Games no longer actively supported by developers and publishers can be maintained and improved by player-made mods. After EA ended support for MVP Baseball 2005, due to losing the license for the Major League Baseball, the game's modding community continued to support it by releasing updated roster lists and graphics mods every year, along with modding alternative baseball leagues for the game. Multiple mods were created for the poorly received 2011 game IL-2 Sturmovik: Cliffs of Dover to fix bugs and gameplay issues; modders later received source code access, culminating in an official re-release of the game. Following the closure of Ion Storm, the source code for Daikatana was released to a select group of modders, who led the version 1.3 patch and ported the game to MacOS, Linux and FreeBSD. Mods are also created for older PC games that are incompatible for modern display resolutions, such as the DXX-Rebirth and DXX-Redux mods for the 1995 game Descent. User interface mod A user interface mod changes parts of how players interact with the game, Mod packs may be created with the purpose of making the original game more accessible to new players or to make the game more challenging for veteran players. ==See also==