Reflex Arena is a fast-paced and competitive online game that tests your reflexes and coordination. It features intense multiplayer battles in a variety of arenas and game modes. You can play with up to 8 players in a single match, or join a team and battle it out with up to 32 players. The game offers a variety of weapons, from traditional guns to futuristic laser guns and gravity guns. You can choose from a variety of game modes, from classic deathmatch to capture the flag and objective-based game modes. The game also features leaderboards and achievements to track your progress. With its fast-paced action and unique game modes, Reflex Arena is sure to provide hours of exciting and intense gaming.
Discontinued No further updates since November 2013: http://assault.cubers.net/ (like Alien Arena, also noted to be discontinued).
Discontinued No more updates since January 2013: http://sauerbraten.org/. 2013, like Alien Arena, warned discontinued.
Discontinued development is not stopped, but the latest version, 0.8.8, was released in February 2012.
Xonotic
Unreal Tournament
Quake
Warsow
Red Eclipse
AssaultCube
Cube 2: Sauerbraten
OpenArena
Discontinued development has been discontinued, as indicated at https://www.warsow.net/forum/thread/17216/1. The latest version, 2.1, released in March 2016, can still be downloaded from the official website.