Mindustry
Factorio-like tower defense game.
Lila
Ad-less chess server powering lichess.org, with official iOS and Android client apps.
Luanti
Voxel game engine (formerly Minetest).
A Dark Room
Minimalist text adventure game for your browser.
OpenTTD
Transport tycoon simulation game.
The Battle for Wesnoth
The Battle for Wesnoth is an Open Source, turn-based tactical strategy game with a high fantasy theme, feat…
Veloren
Multiplayer RPG.
MTA:SA
Add network play functionality to Rockstar North's Grand Theft Auto game series, in which this functionalit…
Hypersomnia
Competitive top-down shooter blending Counter-Strike with Hotline Miami.
Razzia
Quiz game platform, designed for smaller self-hosted events (alternative to Kahoot!).
Zero-K
Open Source on Springrts engine.
DDraceNetwork
Cooperative platformer version of DDRace, a Teeworlds modification featuring unique cooperative gameplay.
Posio
Geography multiplayer game.
Scribble.rs
A web-based pictionary game.
Red Eclipse 2
Arena first-person shooter similar to Unreal Tournament.
Suroi
An open-source 2D battle royale game inspired by surviv.io.
piqueserver
Server for openspades, the first-person shooter in a destructible voxel world.
0 A.D.
Cross-platform real-time strategy game of ancient warfare.
Digibuzzer
Create a virtual game room around a connected buzzer (documentation in French).