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From Pathfinder #163: Ruins of Gauntlight, which isn't enabled.

Bloodsiphon

CREATURE 4
UNIQUEMEDIUMAMPHIBIOUSEVILUNDEADUNHOLY
Perception +10; tremorsense (imprecise) 30 feet
Languages Aklo; cannot speak any language
Skills Athletics +12
Str +4, Dex +1, Con +3, Int -2, Wis +3, Cha -2
Tremorsense 30 feet

Tremorsense allows a monster to feel the vibrations through a solid surface caused by movement. It is an imprecise sense with a limited range (listed in the ability). Tremorsense functions only if the monster is on the same surface as the subject, and only if the subject is moving along (or burrowing through) the surface.

AC 19; Fort +11, Ref +7, Will +11
HP 80, void healing; Immunities bleed, death effects, disease, paralyzed, poison, unconscious; Weaknesses slashing 5
Death Burst (occult)

When the bloodsiphon dies, its body explodes in a cloudy red burst of necrotic dried blood in a 20-foot area.

Creatures in range must attempt a DC 21 Reflex save.

Critical Success The creature is unaffected.

Success The creature takes 2d6 void damage.

Failure The creature takes 4d6 void damage.

Critical Failure The creature takes 6d6 void damage and is Enfeebled 2 for 1 hour.

Void Healing

A creature with void healing draws health from void energy rather than vitality energy. It is damaged by vitality damage and is not healed by vitality healing effects. It does not take void damage, and it is healed by void effects that heal undead.

Speed 10 feet, swim 20 feet
Melee Mouth +14, Damage 2d8+6 piercing plus Grab
Melee Spittle +11, Damage 3d6 void
Blood Drain
Requirements The bloodsiphon has a creature Grabbed or Restrained
Effect The bloodsiphon drains blood from the creature it has grabbed. This deals 4d4 damage and the bloodsiphon grows temporarily moist and slimy as it regains 8 healing Hit Points, gaining any excess as temporary Hit Points that last for 1 minute.

A creature that has its blood drained by the bloodsiphon is Drained 1 until it receives any type of healing.

Grab

Requirements The monster's last action was a successful Strike that lists Grab in its damage entry, or the monster has a creature Grabbed or Restrained
Effect If used after a Strike, the monster attempts to Grapple the creature using the body part it attacked with. This attempt neither applies nor counts toward the creature's multiple attack penalty.

The monster can instead use Grab and choose one creature it's grabbing or restraining with an appendage that has Grab to automatically extend that condition to the end of the monster's next turn.

Pathfinder #163: Ruins of GauntlightOGL