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

Inky Tendrils

COMPLEX HAZARD 20
Stealth +32
Description Six giant tentacles reach up from the ink lake, grabbing any foes in reach and dragging them underwater.

Disable

DC 48 Athletics (legendary) or DC 45 Acrobatics (master) to tie one tentacle into a knot, rendering it useless, or Dispel Magic (8th rank; counteract DC 44) to counteract one tentacle.

The death of the Daemonic Rumormonger permanently dispels all the inky tendrils.


AC 42; Fort +36, Ref +39
Hardness 5, HP 80 (BT 40); Immunities poison

Black Ink Delirium (poison)
Saving Throw DC 38 Fortitude
Maximum Duration 4 rounds
Stage 1 3d6 poison damage and Clumsy 2 (1 round)
Stage 2 6d6 poison damage and Confused (1 round)
Inky Imitator (arcane)

The inky tendrils cast a 10th-rank Duplicate Foe spell (DC 40 Fortitude) on the target; on a failed save, a simulacrum of the target made from dripping ink and clockwork scraps emerges from any other spot (tendrils' choice) in the lake.

The tendrils don't need to Sustain the Spell; the duplicate exists for 1 minute or until it is destroyed before collapsing into a puddle of ink and scrap metal.

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.

Constrict

2d8+10 bludgeoning plus black ink delirium, DC 42 basic Fortitude


The monster deals the listed amount of damage to any number of creatures Grabbed or Restrained by it. Each of those creatures can attempt a basic Fortitude save with the listed DC.

Tendrils Come Alive
Trigger A non-daemonic creature moves within 15 feet of the shoreline

Effect The hazard makes a tentacle Strike against the triggering creature and the hazard rolls initiative.
Melee Tentacle +37 (reach 15), Damage 4d8+15 bludgeoning plus Grab

No multiple attack penalty

Routine (6 actions) The hazard loses 1 action for every tentacle that is disabled or destroyed. The tentacles can combine their actions to use the hazard's Inky Imitator ability. A broken tentacle can still Strike, but it can't Grab. This hazard takes no multiple attack penalty.
Pathfinder #162: Ruins of the Radiant SiegeOGL