Water Elemental Vessel

Spell Circle (mental) — By performing an hour-long ritual, an elemental vessel can form a spell circle with an arcane or primal spellcaster. After the spell circle is formed, other spellcasters can join the spell circle by performing the same hour-long ritual while assisted by at least one spellcaster already in the spell circle. Each member of the spell circle must contribute at least one spell to the elemental vessel. The spellcaster permanently loses access to a spell slot equal to the spell's rank and the elemental vessel adds the contributed spell to its list of arcane innate spells (regardless of the spell's original type). An elemental vessel can be imbued with no more than three spells per spell rank. If the elemental vessel is destroyed, all members of the spell circle regain the spell slots they contributed to the creature. The arcane innate spells shown below represent a typical spell list for an elemental vessel, but each elemental vessel is likely to have different spells depending on what its spell circle has contributed.

Dispel Vulnerability — Whenever a creature successfully counteracts one of its spells, the vessel permanently loses access to that spell and takes damage equal to 4 × the spell's rank. The spell circle member who contributed that spell regains access to their contributed spell slot.

Inhabit Vessel (mental) — Any member of the elemental vessel's spell circle can spend 3 actions to mentally inhabit the vessel for 1 round. While they inhabit the vessel, the inhabiter controls the vessel's actions, and the vessel uses the inhabiter's Intelligence, Wisdom, and Charisma modifiers for all checks. Only one creature can inhabit an elemental vessel at a time.

Engulf — DC 35 Reflex save, no damage, Escape, Rupture 28

The monster Strides up to double its Speed and can move through the spaces of any creatures in its path. Any creature of the monster's size or smaller whose space the monster moves through can attempt a Reflex save with the listed DC to avoid being engulfed. A creature unable to act automatically critically fails this save. If a creature succeeds at its save, it can choose to be either pushed aside (out of the monster's path) or pushed in front of the monster to the end of the monster's movement. The monster can attempt to Engulf the same creature only once in a single use of Engulf. The monster can contain as many creatures as can fit in its space.

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.
Effect: Engulf and Swallow Whole

A creature that gets free by either method can immediately breathe and exits the swallowing monster's space.

If the monster dies, all creatures it has engulfed are automatically released as the monster's form loses cohesion.

Internal Spell Strike — The elemental vessel targets an engulfed creature with one of its spells. The spell must have a range of touch.

Push 10 feet —