The game takes place in the summer of AW 1281, about three years before the events of Phantasy Star II. This chapter features Rudolf "Rudo" Steiner (Rudogā Steiner or Rudger Steiner), who, after heading home while off-duty from the military, finds his wife and child killed, and his hometown devastated after the attack of a mole-like Biomonster. He sets out to hunt the monster down for revenge, leading to his eventual motivation in becoming a hunter dedicated to their extermination. It is implied through the events of this game, as well as his short guest appearance in that of Nei, that after deciding to become a hunter and having encountered Nei sometime afterward, he eventually gains word of Rolf's effort to seek the source of the Biomonster outbreak, resulting in him joining the group.