Due to the lack of official support or standardization of competitive Team Fortress 2, a wide variety of gamemodes have arisen from the community during the game's lifetime. While not all gamemodes are recognized or played on equal footing, all gamemodes feature at least some sort of informal ruleset and have had competitions organized featuring the gamemode.
- Main article: Ultiduo
Ultiduo is a gamemode that features two teams of one Soldier and one Medic, who play on custom Ultiduo maps consisting of one control point. The gamemode is commonly played by players of other gamemodes as a method to practice Soldier and Medic gameplay, alongside MGE.
- Main article: 4v4
- Main article: 6v6
6v6 is the official competitive gamemode of Team Fortress 2. It features two teams of six players, and is known for its traditionally strict ruleset and restrictive map pool, typically only featuring Control Point maps. High-level competitive play is played exclusively in the 6v6 gamemode.
Due to the popularity of 6v6, it has come under intense criticism for its comparatively "stale" gameplay and ruleset, as well as the sparse usage of Specialist classes. Along with variants of 6v6, many other competitive gamemodes were created to address criticism of the 6v6 gamemode specifically.
- Main article: Prolander
Prolander (also known as Pick/Ban Prolander or 7v7) is the flagship competitive gamemode of RGL. It is akin to Highlander, featuring a universal class limit of one, however is played with seven players on each team.
- Main article: Highlander
Highlander (also known as 9v9) is a competitive gamemode played in a 9v9 ruleset, with a universal class limit of one. As such, every class is always in play and is comparatively more analogous to the gameplay of public servers compared to other gamemodes. Highlander is the second-most popular gamemode, second to 6v6, and has been featured at multiple LAN events.