Magic Resistance. The arcanaloth has advantage on saving throws against spells and other magical effects.
Magic Weapons. The arcanaloth's weapon attacks are magical.
Innate Spellcasting. The arcanaloth's innate spellcasting ability is Charisma (spell save DC 15). The arcanaloth can innately cast the following spells, requiring no material components:
At will: alter self, darkness, heat metal, invisibility (self only), magic missile
Spellcasting. The arcanaloth is a 16th-level spellcaster. Its spellcasting ability is Intelligence (spell save DC 17, +9 to hit with spell attacks). The arcanaloth has the following wizard spells prepared:
Cantrips (at will): fire bolt, mage hand, minor illusion, prestidigitation
1st level (4 slots): detect magic, identify, shield, Tenser's floating disk
2nd level (3 slots): detect thoughts, mirror image, phantasmal force, suggestion
3rd level (3 slots): counterspell, fear, fireball
4th level (3 slots): banishment, dimension door
5th level (2 slots): contact other plane, hold monster
6th level (1 slot): chain lightning
7th level (1 slot): finger of death
8th level (1 slot): mind blank
Claws. Melee Weapon Attack: +7 to hit, reach 5 ft., one target. Hit:8 (2d4 + 3) slashing damage. The target must make a DC 14 Constitution saving throw, taking 10 (3d6) poison damage on a failed save, or half as much damage on a successful one.
Teleport. The arcanaloth magically teleports, along with any equipment it is wearing or carrying, up to 60 feet to an unoccupied space it can see.
Yugoloths are fickle fiends that inhabit the planes of Acheron, Gehenna, Hades, and Carceri. They act as mercenaries and are notorious for their shifting loyalties. They are the embodiments of avarice. Before serving under anyone's banner, a yugoloth asks the only question on its mind: What's in it for me?