Serious Sam (Series) AlternativesFirst-Person Shooters and other similar apps like Serious Sam (Series)

Xonotic is a free (GPL), fast-paced first-person multiplayer shooter that works on Windows, OS X and Linux. The project is geared towards providing addictive arena shooter gameplay which is all spawned and driven by the community itself.

Unreal is a series of first-person shooter video games developed by Epic Games.

Quake is a classic first-person shooter game that revolutionized the genre with its fast-paced action and innovative multiplayer modes. Originally released in 1996, it continues to be a beloved title among gamers.

Red Eclipse is a fun-filled new take on the first person arena shooter, built as a total conversion of Cube Engine 2, which lends itself toward a balanced gameplay, with a general theme of agility in a variety of environments.

Cube 2: Sauerbraten is a free multiplayer/singleplayer first person shooter, built as a major redesign of the Cube FPS.

Warsow is a completely free fast-paced first-person shooter (FPS) for Windows, Linux and Mac OS X, set in a futuristic cartoonish world where rocketlauncher-wielding pigs and lasergun-carrying cyberpunks roam the streets.

OpenArena is a community-produced deathmatch FPS based on GPL idTech3 technology. There are many game types supported including Free For All, Capture The Flag, Domination, Overload, Harvester, and more. There are 17 unique player models to choose from and 12 weapons.

Overwatch is a team-based shooter where heroes do battle in a world of conflict.

Urban Terror started as a realism based "total conversion" mod for Quake III Arena. Nowadays, Urban Terror is played using the free, stand-alone, ioquake3 engine modified, which doesn't require Quake III Arena, in addition to being an add-on to id Software's...

Freedoom is a WIP a complete free content game based on the Doom engine. It's not an engine, but it's replacement game data with entirely original content, Compatible with a majority of game mods made for Doom. Comes in Three Flavors~.

The game is inspired by such classic titles as Quake and Doom, with the emphasis on killing large numbers of monsters. The game is divided into five chapters, each about five levels long. The player's objective is to get through each level, from start to finish, by...

Digital Paint: Paintball 2 is a Paintball game that started out as a mod for quake 2 but then took on a life of its own as an open source fps game with a global player and clan management system.