GemRB is a portable open-source implementation of the Infinity Engine
Cooperative multiplayer graphical RPG and adventure game
Arianne is an engine to develop multiplayer online games like Stendhal
Provides a full suite of clients and servers for virtual worlds.
Explore the island, talk to it's inhabitants and discover it's secrets
Mud Server in Python Language playable via web browser
Top-down dungeon crawler
LAIR is a Sandbox Dungeon Crawling Game
A Dungeons & Dragons Miniature Game.
Server software written in Python that implements the MUCK protocol.
Scriptable GTK based Python MUD Client
A free Python 3 text-based MUD game server