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From Pathfinder #168: King of the Mountain, which isn't enabled.

Yabin (White Serpent Form)

CREATURE 18
UNIQUEMEDIUMEVILHUMANOIDNAGAJI

Dimensional superposition form of Yabin the Just

Perception +28; darkvision
Languages Nagaji, Taldane, Tengu, Tien; (can't speak any language)
Skills Acrobatics +31, Athletics +35, Diplomacy +31, Intimidation +37, Occultism +31
Str +3, Dex +5, Con +6, Int +3, Wis +2, Cha +6
Poisonous Floodwaters (aura, poison, water)

10 feet. Yabin is surrounded by magically generated waist-deep poisonous waters. Enemies that enter the water are exposed to his white serpent venom. The aura is difficult terrain for creatures without a swim Speed. Every time Yabin Casts a Spell, the aura increases in radius by 5 feet, up to a maximum of 60 feet. He can activate or suppress this aura as a single action, which has the concentrate trait.

Rattling Magic

Yabin substitutes all spellcasting components when Casting a Spell with rattling of his tail. This has the concentrate trait.

Toughest Teamwork: Envenomed Strike
Trigger An ally within 20 feet makes a Strike that would deal piercing or slashing damage and hasn't yet rolled the attack roll
Effect Yabin spits venom on his ally's weapon. The Strike, if it hits, also exposes the target to Yabin's white serpent venom. If the Strike misses, the venom evaporates off immediately.
White Serpent Venom (poison, virulent)
Saving Throw DC 36 Fortitude
Maximum Duration 6 rounds
Stage 1 3d6 poison damage (1 round)
Stage 2 5d6 poison damage and Dazzled (1 round)
Stage 3 5d6 poison damage and Blinded (1 round)
AC 39; Fort +30, Ref +28, Will +33
HP 256; Immunities poison
Speed 25 feet, burrow 20 feet, swim 60 feet
Melee Fangs +33 (finesse, reach 10), Damage 4d10+11 piercing plus White Serpent Venom
Melee Venom +33, Damage 4d8+8 poison plus White Serpent Venom
Spontaneous Arcane Spells DC 40, attack +32; 9th (4 slots) Dispel Magic, Magic Missile, Polar Ray; 8th (4 slots) Disappearance, Horrid Wilting, Prismatic Wall, Scintillating Pattern; 7th (4 slots) Disintegrate, Eclipse Burst, Mask of Terror, True Seeing; 6th (4 slots) Chain Lightning, Feeblemind, Fireball, Spellwrack; 5th (4 slots) Chromatic Wall, Cloak of Colors, Freedom of Movement, Haste; Cantrips (9th) Acid Splash, Detect Magic, Light, Shield, Telekinetic Projectile
Pathfinder #168: King of the MountainOGL