Fiendish Blessing. The AC of Abraxis includes his Charisma bonus.

Innate Spellcasting. Abraxis’s spellcasting ability is Charisma (spell save DC 18). Abraxis can innately cast the following spells, requiring no material components: 

At will: misty step, command

3/day each: alter self, detect magic, dimension door, fireball (5th level)

1/day: plane shift (self only), reverse gravity, teleport 

Multiattack. Abraxis makes two melee attacks or uses his Fire Ray twice.

Silvered Abyssal Longswords. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 10 (1d10 + 5) slashing damage plus 22 (4d10) fire damage.

Fire Ray. Ranged Spell Attack: +10 to hit, range 120 ft., one target. Hit: 13 (3d8) fire damage.

Silver Tongue. One humanoid Abraxis can see within 30 feet of himself must succeed on a DC 18 Wisdom saving throw or be magically charmed for 1 day. The charmed target obeys Abraxis’ spoken commands. If the target suffers any harm from Abraxis or another creature or receives a suicidal command, the target can repeat the saving throw, ending the effect on itself on a success. If a target’s saving throw is successful, or if the effect ends for it, the creature is immune to Abraxis’ Silver Tongue for the next 24 hours.