From the introduction: Caverns of the Goblin King is intended for four characters with an average party level (APL) of 8. Characters who complete this adventure should earn enough experience to reach halfway to 7th-level. A tribe of goblins has been waylaying passing caravans. This campaign takes place in Arden, although it can be set in your own world. Any party composition should be able to finish the adventure with intelligent play.