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From Pathfinder #164: Hands of the Devil, which isn't enabled.

Sacuishu

CREATURE 9

Female will-o'-wisp spy

Perception +21; darkvision
Languages Aklo, Common, Diabolic, Sakvroth
Skills Acrobatics +19, Deception +17, Intimidation +17, Religion +19, Stealth +19
Str -5, Dex +6, Con +0, Int +3, Wis +6, Cha +4

AC 30; Fort +16, Ref +18, Will +20
HP 80
Glow (aura, light)

20 feet. Sacuishu is naturally Invisible but glows with a sickly green light, casting bright light in the aura and making her visible.

Magic Immunity

Sacuishu is immune to all spells except Faerie Fire, Revealing Light, Force Barrage, and Quandary.


Speed fly 50 feet
Melee Shock +21 (electricity, magical), Damage 2d8+8 electricity
Feed on Magic (concentrate)
Requirement A creature who can cast spells is within 15 feet of Sacuishu

Effect Sacuishu feeds on the creature's magic. Sacuishu regains 2d8 healing Hit Points, and the target must attempt a DC 28 Will save. The target is then temporarily immune for 1 hour.

Critical Success The target is unaffected.

Success The first time the target Casts a Spell before the start of the Sacuishu's next turn, the spell is disrupted unless the target succeeds at a DC 15 flat check check.

Failure As success, but the effect applies the first time the target Casts a Spell within the next minute.

Critical Failure As success, but the effect applies each time the target Casts a Spell within the next minute. In addition, Sacuishu doubles the Hit Points it regains

Go Dark (concentrate)

Sacuishu extinguishes her glow, becoming Invisible. She can end this effect with another use of this action. If she uses her shock attack while invisible, the arc of electricity lets any observer determine her location, making Sacuishu Hidden to observers only until she moves.

Pathfinder #164: Hands of the DevilOGL