From the introduction: Time Spiral: Volume 1 is intended for four characters with an average party level (APL) of 1. Characters who complete this adventure should earn enough experience to reach halfway to 5th-level. In order to avert a catastrophe, a wizard sends a group of heroes back in time. 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.