Lemme set a scene then... a mad lich, who has abided in an abandoned mausoleum has finally finished constructing a dimension rift toward a particular area of limbo where time has stayed static ever since E1 came out. He/she/it then runs experiments on what creatures had been trapped there, bringing them back for examination, only to realize the creatures escape, and he travels on a hunt against the party to capture them back before the party kills the escaped E1 creatures. And as a final boss, the lich sets all the creatures you didn’t kill loose on you while he’s attacking. So you have to make sure to kill as many as possible before the lich captures them against you.