Multi Theft Auto is a game engine
Open source clone of the Age of Empires II engine
The Tiny JavaScript Game Engine That Can!
The Open Toolkit library is a fast, low-level C# wrapper for OpenGL
Powerful, mature open-source cross-platform game engine for Python
Embeddable unity game engine view for Flutter
A simple tool to allow Chessmaster 10/11 bot customizations
Data-oriented and data-driven game engine written in Rust
scriptable game engine with built-in support for 2D graphics and sound
Multi-threaded game engine for Android
Egret is a brand new open mobile game and application engine
A runtime-programmable, cross platform, game engine
XNA based game engine completely written in c#
TR Game Engine allows you to develop your game quickly and easily.
A retro style video game engine for RPGs and adventure games.
A lightweight HTML5 Game Engine