school of demonology

demonologist are masters of fiends and dark powers they know secrets no mortal should know and are rejected and shunned by most other wizards demonology is a taboo almost every were the only places they go are the dark areas of the world were fiends are worshipped were they can conduct their studies without being attacked by hordes of angry villagers

Demonologist are expert of fiends and how to control them. Despite their name, demonologist are not needed to be servant of demonkind, in fact a lot of lawful evil demonologist serve devils as expert at fighting and controlling demonkind or rival devils. Very very rarely a demonologist is good, seeking to use the power of fiendss against them, which rarely end well for anyone involved.

fiendish thralls

fiendish thralls g when you select this tradition at 2nd level, whenever you gain a wizard level, you can replace one of the wizard spells you add to your spellbook with a warlock spell. The spell must be of a level for which you have spell slots. 

only other demonologists can copy your warlock spell from your book.

you have advantage on all attempts to recall lore about fiends 

corrupt spells

Beginning at 2nd level, 3 times a day when you cast a damaging spell targeting another creature you can add 1d4 fire or necrotic damage equal to your charisma modifier 

fiendish thralls

Starting at 6th level, 

At 6th level, you add the summon lesser demons spell to your spellbook if it is not there already. When you cast summon lesser demons, you can control all the creatures you summon and when you cast a spell that summons or dominates a fiend you roll with advantage and give your proficiencies to the fiends 

 

dark empowerment

Beginning at 10th level, You can use your charisma score as your spell casting casting ability instead of int and can add your charisma modifier to your armor class

bind fiend

Starting at 14th level, you can use magic to bring fiends under your control, even those summoned by other wizards. As an action, you can choose one fiends that you can see within 60 feet of you. the creatures challenge rating cannot be over your charisma score That creature must make a Charisma saving throw against your wizard spell save DC+ your charisma mod. If it succeeds, you can't use this feature on it again. If it fails, it becomes friendly to you and obeys your commands until you use this feature again.

you can only have a maximum of fiends under your control equal to your charisma mod