Arianne is an engine to develop multiplayer online games like Stendhal
2D Game Engine
IRB is a game creation toolkit
Processes dialogue text files exported by the Bethesda Softworks SDK
Built to be ease of use, with no programming knowledge, Multi-platform
A 2D Adventure Game & Engine
TurboSphere is an easy to learn and powerful JS based game engine.
A retro style video game engine for RPGs and adventure games.
Framework for a graphical point and click adventure game in Java
Cross-platform 2D game engine
Andruill Engine is a GMS (Game Management System) written in PHP.