Svelto ECS C# Entity Component System
Entitas is a super fast Entity Component System (ECS) Framework
3D C++ Game Engine - yet another open source game engine
RPG dice roll simulator for vintage Tandy TRS-80 100/102/200 laptops
Clojure in Unity
A roguelike game engine/editor
XNA based game engine completely written in c#
RPG Games without coding!
Cross-platform 2D game engine