Arianne is an engine to develop multiplayer online games like Stendhal
Opengate is a Jumpgate remake
GemRB is a portable open-source implementation of the Infinity Engine
General Purpose Engine for Graphic Adventures.
InterBBS medieval door game
Open-source reimplementation of the original King's Bounty
Defeat all the beasties to claim victory!
The ECE is for creation and managing ED3+ED4 characters.
Ur-Quan Masters High Definition
low fantasy cRPG
A complete web framework to create online Fighting Fantasy adventures
Free MMORPG
A graphical frontend for PbeM like Eressea