Ct.js is a desktop game engine that makes learning programming fun
Free game engine for development of desktop, mobile, and web games
3D Game engine with editor
KorGE Game Engine. Multiplatform Kotlin Game Engine & Korlibs
Stride (formerly Xenko), a free and open-source cross-platform C# game
The flexible game engine
The Tiny JavaScript Game Engine That Can!
Descent 3 by Outrage Entertainment
A cross-platform, open-source, pure C game engine for mobile game
Web powered cross-platform 3D, WebXR game engine
Multi-platform game engine similar to old Megaman with a stage editor