Cambion Warlock of the Fiend

Fiendish Blessing. The AC of the cambion includes its Charisma bonus.

Innate Spellcasting. The cambion’s spellcasting ability is Charisma (spell save DC 16). The cambion can innately cast the following spells, requiring no material components:

At will: false life, levitate (self only), mage armor (self only), silent image, speak with dead
3/day each: alter self, command, detect magic

Spellcasting. The cambion is a 17th-level spellcaster. Its spellcasting ability is Charisma (spell save DC 16, +8to hit with spell attacks). It regains its expended spell slots when it finishes a short or long rest. It knows the following warlock spells:
Cantrips (at will): eldritch blast, friends, mage hand, minor illusion, poison spray, prestidigitation, shocking grasp
1st level-5th level (4 5th-level slots): banishment, burning hands, fireball, flame strike, hellish rebuke, magic circle, mirror image, scorching ray, scrying, wall of fire
1/day each: feeblemind, finger of death, plane shift (self only)

Dark One's Own Luck (Recharges after a Short or Long Rest). When the cambion makes an ability check or saving throw, it can add a 1d10 to the roll. It can do this after the roll is made but before any of the roll's effects occur.

Multiattack. The cambion makes two melee attacks or uses its Fire Ray twice.

Spear. Melee or Ranged Weapon Attack: +6 to hit, reach 5 ft. or range 20/60 ft., one target. Hit: 5 (1d6 + 2) piercing damage, or 6 (1d8 + 2) piercing damage if used with two hands to make a melee attack, plus 3 (1d6) fire damage.

Fire Ray. Ranged Spell Attack: +8 to hit, range 120 ft., one target. Hit: 10 (3d6) fire damage.

Fiendish Charm. One humanoid the cambion can see within 30 feet of it must succeed on a DC 16 Wisdom saving throw or be magically charmed for 1 day. The charmed target obeys the cambion’s spoken commands. If the target suffers any harm from the cambion or another creature or receives a suicidal command from the cambion, 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 the cambion’s Fiendish Charm for the next 24 hours.