Modified source engine (2017) developed by valve and leaked in 2020
A book reader for Nintendo DS
Urho3D Game engine
Nestopia UE
Updated emulator of Forgotten Realms: Unlimited Adventures
Mini game engine for games104
Real-time collision detection and multi-physics simulation for VR
A simulator for drones, cars and more, built on Unreal Engine
A fork of dhewm3 with an emphasis on modernisation and vanilla Doom 3
Another clone of Rick Dangerous classic game
Spring is a free RTS engine developed for Windows, Linux and Mac OS X.
3D C++ Game Engine - yet another open source game engine
Graphical hook for a D3D9-D3D12, OpenGL and Vulkan based games
Improved version of the X-Ray Engine, the game engine
DeSmuME is a Nintendo DS emulator
A 2D game engine and level editor
A mapping tool for text-based games like text adventures, MUDs, etc.
MAME Android Emulator.
KlayGE is a cross-platform open source game engine
A cross-platform 2D game engine
Retro Games in Gym