Summoners work their magic by opening doorways to different planes of existence. Usually this is to bring forth creatures from these other planes to use as servants, although there are other ways to use this power. It is perhaps worth mentioning that the term ‘demon’ refers to any being from another plane of existence. Demons are not all necessarily evil, nor do they all have horns or hooves. That said, demons are not usually happy about being summoned, and the life of a Summoner is a dangerous one.