Xen cave interior with glowing plants — Half-Life: Enriched mod

Black Mesa: Classic is an ambitious fan project aimed at porting the Black Mesa remake (on the Source engine) back to the original GoldSrc engine from Half-Life. The mod restores the atmosphere of the original game while adding a number of improvements and maintaining low system requirements.

Diamond Dragon is a stylish gameplay mod for Doom II in a cyberpunk aesthetic, where you play as Kiwi, a cybernetic catgirl hunter. The mod combines fast-paced action, firearms, and a katana, allowing you to freely choose your combat style — from pure melee to shooter.

OpenNox is an open-source game engine that is the result of collaborative community work. Its main goal is to extend and improve the original game Nox.

Crystallized Doom is a mod for OpenRA based on a modification for Tiberian Sun. It significantly expands the combat system and adds research mechanics and subfactions depending on the chosen side. Among the planned factions are GDI, Nod, Cabal, Forgotten, Scrin, and Seraphs.

Diablo I HD Mod (Belzebub) is a large-scale mod for the original Diablo that adds HD resolution support, new character classes, restored quests, an improved interface, and numerous gameplay enhancements.