TrueCombat: Elite & CQB Alternatives for Linux

Xonotic is a fast-paced, arena-style first-person shooter with a focus on pure competitive gameplay. It is free, open-source, and offers both single-player and robust multiplayer modes with a variety of weapons and game types.

Cube 2: Sauerbraten is a fast-paced, Quake-inspired open-source first-person shooter with a unique in-game map editor and strong multiplayer focus. It emphasizes quick movement and tactical team-based gameplay.

OpenArena is a free and open-source standalone 3D first-person shooter game. It is a community-developed clone of Quake III Arena, offering fast-paced multiplayer and single-player combat with a variety of weapons and game modes.

Urban Terror is a free-to-play, multiplayer first-person shooter that balances realism with fast-paced action. Built on a modified ioquake3 engine, it offers a competitive experience with diverse maps, weapons, and gameplay modes.