Epic story-driven FPS running on the Build Engine

Dhewm 3 is a Doom 3 GPL source port

Source port for Build engine games

Leading the way in newschool multiplayer Doom online

Free agile arena shooter

A Zandronum 3.0 fork with improved netcode, configurable movement and many small tweaks

Open Source voxel shooter

A modern cross‑platform port of “STAR WARS™: Dark Forces” with mod support

Tank digging battle game

Yamagi Quake II is an alternative client for id Software's Quake II

A Doom II mod with weapons and mechanics inspired by Quake Champions

Aliens vs Humans, First Person Shooter game with elements of Real Time Strategy

Classic arena first person shooter

a modern QuakeWorld client focused on competitive online play

First-person shooter game

FPS aim trainer

Fast arcade first person shooter

A modernization effort of DOOM-3-BFG

Modern cross-platform port of the Descent engine

A Quake mod based on the retro shooter SPRAWL

Fast paced, first person strategy game

Open Source voxel shooter

The Free and Fast Arena Shooter

Game engine for Classic Doom

EDuke32 is an awesome, free homebrew game engine

The orb ponderer's arena first-person shooter

Free fast paced arena shooter

Shoot and survive

ReC98 source port of the first Seihou Project game

Top-down shooter action RPG