Dark interior room with Quake weapons and mask in LibreQuake fan game

Painkiller: Mutilator is a gameplay mod for Doom that brings the weapons and monsters of Painkiller to any Doom map. The mod features 3D weapons with alternate fire modes, hordes of familiar monsters, soul collection for a demon mode, as well as headshots, gibs, and a grappling hook.

TERMINATOR DOOM is a gameplay mod for Doom that lets you play as the T-800 Terminator: an unstoppable killing machine with weapons from the Terminator film series, enhanced melee combat, vision modes, and the ability to deliver iconic quotes right during battle.

ZMenu FlatOut 2 + Chaos Mod is a powerful trainer for FlatOut, featuring Chaos Mod, god mode, infinite nitro, free camera, wall driving, air control, teleportation, VR support, and much more.

Red Alert 2: Apocalypse is a large-scale mod for Yuri's Revenge that reimagines the original game, adding dozens of new units, buildings, and superweapons and reworking the balance while preserving the classic atmosphere.

C&C: Brute Force is a mod for Yuri's Revenge that turns the game into a kind of Tower Defense: you start with minimal forces, defend against endless waves of Yuri's minions, find random supplies, and gradually strengthen your base to eventually reach the dictator himself.