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From Pathfinder #162: Ruins of the Radiant Siege, which isn't enabled.

Nenchuuj

CREATURE 19
UNCOMMONMEDIUMEVILFIENDSAHKILUNHOLY
Perception +33; darkvision; detect magic
Languages Chthonian, Diabolic, Empyrean, Requian; telepathy 100 feet
Skills Acrobatics +33, Arcana +39, Deception +33, Dream Lore +33, Intimidation +37, Occultism +37, Stealth +33
Str +5, Dex +8, Con +6, Int +10, Wis +6, Cha +8
Telepathy 100 feet (aura, magical)

A monster with telepathy can communicate mentally with any creatures within the listed radius, as long as they share a language. This doesn't give any special access to their thoughts, and communicates no more information than normal speech would.

Constant Spells

A constant spell affects the monster without the monster needing to cast it, and its duration is unlimited. If a constant spell gets counteracted, the monster can reactivate it by spending the normal spellcasting actions the spell requires.

AC 43; Fort +31, Ref +29, Will +37; +2 status to all saves vs. magic
HP 355; Immunities death effects, fear effects; Weaknesses holy 15
+2 Status to All Saves vs. Magic
Distort Magic (divine)
Trigger A creature targets the nenchuuj with a spell
Effect The nenchuuj warps the creature's magic, attempting an Arcana check to counteract the spell. If successful, the nenchuuj can instead redirect the spell, as Spell Turning, onto the caster or onto a different target within range from the caster.
Easy to Call

The sahkil is considered 2 levels lower for the purposes of being summoned by rituals (such as Binding Circle), but is always free to attack or leave instead of negotiate unless the primary caster's check is a critical success.

Speed 50 feet, air walk 25 feet
Melee Fist +35 (agile, finesse, magical, unarmed, unholy), Damage 4d8+13 bludgeoning plus 5d6 spirit
Ranged Mindtwisting Utterance +36 (auditory, magical, mental, unholy, range increment 100 feet), Damage 4d12 mental plus 5d6 spirit
Divine Innate Spells DC 41, attack +33; 9th Dispel Magic (At Will), Weird, Mask of Terror (Constant) (See Tainted Backlash); 8th Mind Blank; 4th Fear (At Will), Freedom of Movement, Nightmare (At Will); Cantrips (10th) Detect Magic (Constant); Constant (9th) Air Walk
Skip Between (divine, teleportation)

The sahkil can move itself between the Ethereal Plane and the Material Plane, as Ethereal Jaunt, except that this ability has an unlimited duration and can be Dismissed.

Tainted Backlash

A creature Frightened by the sahkil's Mask of Terror is gripped with fear of the ways magic can go wrong.

The creature is Stupefied 2 for as long as it is frightened. If the creature Casts a Spell during its turn, it can't reduce its frightened condition at the end of that turn.

Pathfinder #162: Ruins of the Radiant SiegeOGL