Ct.js is a desktop game engine that makes learning programming fun
Free game engine for development of desktop, mobile, and web games
Magic Another Game Engine
3D Game engine with editor
Stride (formerly Xenko), a free and open-source cross-platform C# game
KorGE Game Engine. Multiplatform Kotlin Game Engine & Korlibs
A fresh & lightweight javascript game engine
The flexible game engine
The Tiny JavaScript Game Engine That Can!
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D
An OpenGL RTS game engine written in C
Descent 3 by Outrage Entertainment
Game engine supporting many 3D/2D formats and graphic effects
Haskell game engine library for roguelike dungeon crawlers
A cross-platform, open-source, pure C game engine for mobile game
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
Web powered cross-platform 3D, WebXR game engine
Multi-platform game engine similar to old Megaman with a stage editor