# Hearts, Clubs, Diamonds, Spades: Players Who Suit MUDs

- **Author**: Richard Bartle
- **Year**: 1996
- **Summary**: This influential paper proposes a taxonomy of MUD (Multi-User Dungeon) players, classifying them into four types: Achievers (who focus on points and rising through levels), Explorers (who enjoy discovering the game world), Socializers (who prioritize interaction with other players), and Killers (who thrive on competition and causing distress to others). This framework is widely used to design gamified systems that appeal to different user motivations.
- **Link**: https://mud.co.uk/richard/hcds.htm
