Revenge appears when a player kills the player that killed him/her for 5 times in a match (aka Domination) in Deathmatch, Team Deathmatch or Gun Deathmatch in Counter-Strike Online. Any revenge kills that is performed in a room with at least 4 players will count towards the medal Incarnation of Jealousy's progress.
While the pop-up and the sound does not appear in Gun Deathmatch, the general rule still applies, and the player can still get a Revenge kill in Gun Deathmatch.
- Revenge is similar to Team Fortress 2 domination system by Valve Corporation. But, there are some differences. A sound effect will be played for both domination and revenge. The player's character will give a response to both domination and revenge by voice or a laughter. Dominating a player takes one kill lesser than Counter-Strike Online.