A 2D rigid body physics engine for the web
Zig game engine & graphics toolkit
JavaScript-based game engine designed to empower developers
GemRB is a portable open-source implementation of the Infinity Engine
Game engine supporting many 3D/2D formats and graphic effects
SDL based generic 2D game engine
The multiplayer game engine
DOOM / Heretic / Hexen source port with enhanced graphics and UI
Amazon Lumberyard is a free AAA game engine
A cross platform Lua based game engine
Web powered cross-platform 3D, WebXR game engine
Portable game engine with main focus on point-and-click adventures
Multi-platform game engine similar to old Megaman with a stage editor
Java decentralized cross-platform network multiplayer game engine
A multiplatform game engine for interactive fiction experiences