ErisMUD is a MUD engine written from scratch in Python using SQLite for storing data. ErisMUD started in 2004 and is distributed under the GPL (a copy of the license can be found in the README file, in the releases.)
ErisMUD is a work-in-progress but already has many features:

• Creating/destroying/listing rooms, items, NPCs with a single command.
  
• Adding aliases to objects.
• Optional ANSI colors.
• MUD-wide chat system.
• Cloning items, dropping them on the floor, getting them, giving them to other players.
• Instances: a single object may be cloned multiple times and every instance is independent.
• Easily add or modify help files with a single command.
• Logging.

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