Skill-based matchmaking

A common rating system in chess is the Elo rating system, developed by Arpad Elo. Former International Chess Federation president Florencio Campomanes described it as an "inseparable partner to high-level chess".[1] In 2006, Microsoft researchers proposed a skill-based rating system using Bayesian inference and deployed it on the Xbox Live network, then one of the largest deployments of a Bayesian inference algorithm.[2] The researchers were displeased with the ranking system in the beta of Halo 2 (2004).[3] By the time Halo 2 launched, it was using TrueSkill.[4]

The term skill-based matchmaking first appeared in a 2008 interview with game designer John Carmack in which he emphasized its importance in Quake Live (2010). Upon setting up an account with id Software, the game will ask the player for their skill level and judge accordingly depending on their performance from that point forward.[5] The presence—or lack thereof—of skill-based matchmaking became a point of contention. During the development of Dota 2 (2013), Valve Software believed that the barrier to entry could be solved with, among other things, skill-based matchmaking through its Steamworks service;[6] when Call of Duty: Black Ops (2010) developer Treyarch was asked why the game wouldn't include skill-based matchmaking unlike Halo 3 (2007), multiplayer design director David Vonderhaar said that speed was "more important than anything else".[7]

Team-based, competitive games such as League of Legends (2009), Counter-Strike: Global Offensive (2012), Dota 2 (2013), and Overwatch (2016) benefit from skill-based matchmaking. In contrast, Call of Duty: Black Ops II (2012)—a game that primarily focuses on single-player accomplishments—does not benefit from skill-based matchmaking.[8] Treyarch, who developed Call of Duty: Black Ops II, consciously queued players exclusively using ping and latency, in a subversion of industry standards at the time.[9]

Skill-based matchmaking is a controversial practice. In Call of Duty: Warzone (2020), streamers of the game often seek out "bot lobbies"—lobbies with less-skilled players. The Washington Post compared the practice to "LeBron James looking to join pickup games at the local YMCA". Call of Duty: Warzone players who have spoken out against the game's use of skill-based matchmaking include 100 Thieves CEO Nadeshot, former professional Counter-Strike: Global Offensive player Shroud, and 100 Thieves co-owner CouRage. Competitive Call of Duty: Warzone player HusKerrs wrote that high-skilled players must "sweat or try hard" in order to create engaging content.[17] Streamer TimTheTatman refused to stream Call of Duty: Modern Warfare 2 (2022) upon discovering that it would implement skill-based matchmaking.[18]

In February 2023, Destiny 2 (2017) introduced skill-based matchmaking. Higher-skilled players subsequently discovered a way to enter lobbies with lower-skilled players, resulting in outcry from the community.[19]