Complex sentence: Ragnarök is a highly interactive text-based online computer game (played using the Telnet protocol), known as a MUD (Multi-User Dungeon) that was started in 1992 and housed on a server in Portland, Oregon.
Split into simpler sentences: Ragnarök is an interactive text-based online computer game, known as a MUD (Multi-User Dungeon). It was started in 1992 and housed on a server in Portland, Oregon.