Medium fiend (yugoloth), Neutral Evil
| Armor Class | 17 (natural armor) |
|---|---|
| Hit Points | 104 (16d8 + 32) |
| Speed | 30 ft., fly 30 ft. |
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 17 (+3) | 12 (+1) | 14 (+2) | 20 (+5) | 16 (+3) | 17 (+3) |
| Saving Throws | Cha +7, Dex +5, Int +9, Wis +7 |
|---|---|
| Skills | Arcana +13, Deception +11, Insight +11, Perception +7 |
| Damage Vulnerabilities | — |
| Damage Resistances | cold; fire; lightning; bludgeoning, piercing, slashing from nonmagical attacks |
| Damage Immunities | acid; poison |
| Condition Immunities | charmed; poisoned |
| Senses | truesight 120 ft., passive Perception 17 |
| Languages | all, telepathy 120 ft. |
| Challenge | 12 |
The arcanaloth has advantage on saving throws against spells and other magical effects.
The arcanaloth's weapon attacks are magical.
Melee Attack Roll: +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.
The arcanaloth magically teleports, along with any equipment it is wearing or carrying, up to 60 feet to an unoccupied space it can see.
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
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: fire bolt, mage hand, minor illusion, prestidigitation
Level 1 (4 slots): detect magic, identify, shield, Tenser's floating disk
Level 2 (3 slots): detect thoughts, mirror image, phantasmal force, suggestion
Level 3 (3 slots): counterspell, fear, fireball
Level 4 (3 slots): banishment, dimension door
Level 5 (2 slots): contact other plane, hold monster
Level 6 (1 slots): chain lightning
Level 7 (1 slots): finger of death
Level 8 (1 slots): mind blank
Medium fiend (yugoloth), Neutral Evil
| Armor Class | 18 |
|---|---|
| Hit Points | 175 (27d8 + 54) |
| Speed | 30 ft., fly 30 ft. (hover) |
| STR | DEX | CON | INT | WIS | CHA |
|---|---|---|---|---|---|
| 17 (+3) | 12 (+1) | 14 (+2) | 20 (+5) | 16 (+3) | 17 (+3) |
| Saving Throws | Con +6, Dex +5, Int +9, Wis +7 |
|---|---|
| Skills | Arcana +9, Deception +7, Insight +7, Perception +7 |
| Damage Vulnerabilities | — |
| Damage Resistances | cold; fire; lightning |
| Damage Immunities | acid; poison |
| Condition Immunities | charmed; poisoned |
| Senses | Truesight 120 ft., passive Perception 17 |
| Languages | all; telepathy 120 ft. |
| Challenge | 12 |
If the arcanaloth dies outside Gehenna, its body dissolves into ichor, and it gains a new body instantly and revives with all its Hit Points in Gehenna.
The arcanaloth has Advantage on saving throws against spells and other magical effects.
The arcanaloth has a magic tome. While holding or carrying the tome, the arcanaloth can use its Banishing Claw action.
The tome has AC 17; HP 35; and Immunity to Necrotic, Poison, and Psychic damage. The tome regains all its Hit Points at the end of every turn, but it turns to dust if reduced to 0 Hit Points or when the arcanaloth dies. If the tome is destroyed, the arcanaloth can create a new one when it finishes a Short Rest or Long Rest.
The arcanaloth makes three Fiendish Burst attacks. It can replace one attack with a Banishing Claw attack.
Melee or Ranged Attack Roll: +9, reach 5 ft. or range 120 ft. Hit: 31 (4d12 + 5) Necrotic damage.
Melee Attack Roll: +9, reach 5 ft. Hit: 10 (2d4 + 5) Slashing damage plus 19 (3d12) Psychic damage. If the target is a creature, it is subjected to the following effect. cha DC 17. Failure: The target is trapped in a demiplane inside the Soul Tome. While trapped there, the target has the Incapacitated condition. At the end of each of its turns, the target repeats the save, escaping the tome on a success. When the target escapes, it appears in the space it left or, if that space is occupied, the nearest unoccupied space.
If the target fails three of these saves while in the demiplane, it becomes bound to the tome and can escape only if the tome is reduced to 0 Hit Points.
The arcanaloth casts one of the following spells, requiring no Material components and using Intelligence as the spellcasting ability (spell save DC 17):
At will: Alter Self, Detect Magic, Identify, Mage Hand, Prestidigitation
1 each/day: Contact Other Plane, Detect Thoughts, Dimension Door, Mind Blank
The arcanaloth casts Counterspell in response to that spell's trigger, using the same spellcasting ability as Spellcasting.
At will: Counterspell