Engulf [two-actions]
A creature that fails its save is pulled into the monster's body. It is grabbed, is slowed 1, and has to hold its breath or start suffocating. The creature takes the listed amount of damage when first engulfed and at the end of each of its turns while it's engulfed. An engulfed creature can get free by Escaping against the listed Escape DC. An engulfed creature can attack the monster engulfing it, but only with unarmed attacks or with weapons of light Bulk or less. The engulfing creature is off-guard against the attack. If the monster takes piercing or slashing damage equaling or exceeding the listed Rupture value from a single attack or spell, the engulfed creature cuts itself free. A creature that gets free by either method can immediately breathe and exits the engulfing monster's space.
If the monster dies, all creatures it has engulfed are automatically released as the monster's form loses cohesion.