EDIT 2019: This is really due for a revision. I like the overall concept of this, so I’ll probably create something in the near future. After all, why should the warlock have all of the diabolical fun!?
Throughout the ages, many schools of magic have been created and also destroyed. Some have come under attack due to ignorance; arts such as Necromancy and Enchantment have been targeted in particular. Among the most notorious is the art of magic inspired by fiends. The school of Diabolism is such an art, where contact with dark planes leads to manipulating vile energies into wholly new effects.dedicated to dark gods and demonic creatures. While many styles of magic are unlawfully targeted and discriminated against, the diabolists are almost always cruel and wicked.
While pacts with otherworldly beings are the results of enslavement, diabolic mages intentionally scour obscure tomes and demonic rites to enhance their magical craft. Some are connected to patrons like warlocks, while others steal devilish secrets for their own purposes. Warlocks forge direct deals with fiendish beings. Meanwhile, most Diabolists cheat their way into obtaining fiendish magic, often resulting in horrific consequences. That said, many Diabolists are active within cults and truly follow their infernal agenda to its fullest extent.