Cambion Assassin

Assassinate. During its first turn, the assassin has advantage on attack rolls against any creature that hasn't taken a turn. Any hit the assassin scores against a surprised creature is a critical hit.

Evasion. If the assassin is subjected to an effect that allows it to make a Dexterity saving throw to take only half damage, the assassin instead takes no damage if it succeeds on the saving throw, and only half damage if it fails.

Sneak Attack. Once per turn, the assassin deals an extra 14 (4d6) damage when it hits a target with a weapon attack and has advantage on the attack roll, or when the target is within 5 feet of an ally of the assassin that isn't incapacitated and the assassin doesn't have disadvantage on the attack roll..

Innate Spellcasting. The cambion’s spellcasting ability is Charisma (spell save DC 14). The cambion can innately cast the following spells, requiring no material components:

3/day each: alter self, command, detect magic

1/day: plane shift (self only)

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

Multiattack. The assassin makes two shortsword attacks or uses its Fire Ray twice.

Shortsword. Melee Weapon Attack: +6 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) piercing damage, and the target must make a DC 15 Constitution saving throw, taking 24 (7d6) poison damage on a failed save, or half as much damage on a successful one.

Fire Ray. Ranged Spell Attack: +7 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 14 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.