Black Flame

This creature can teleport anywhere using a bonus action, the area which he teleports to is engulfed with flame dealing 2d6 fire damage in a ten foot radius, DC to avoid is 15 dex saving throw. On a succeeding saving throw those within afflicted take half and are not pushed back ten five feet. On a failed targets take 2d6 fire damage and are push back five feet. 

Black Flame can cast Fire Wall which deals 8d8 fire damage. 

Action Name. Black flame has three actions 

Action Melee Attack. Greatsword +5 to hit. Deals additional  1d4 necrotic damage. 2d6 slashing  

Action Ranged Attack. As a bonus action this fiend may send two streaks of black streaks that deals 2d4 necrotic and 2d6 fire damage.

Reaction Name. Using it's reaction Black Flame may summon a Wraith Warrior during this time Black Flame is incapacitated and protected by a shield until the Wraith Warrior dies. 

Nameless Flame: While Bloodied Black Flame may call upon its Patron the Nameless One and engulf the area around it 5 ft radius dealing 1d6 fire damage. The Black Flame heals 10 health points this ability may be used once a day.