Anyu's Spirit Oasis (Arteria)

While you are touching a body of water you call upon Hyran a spirit of the ocean and Miroi a spirit of the moon. The water surrounds you becoming part of your mass, changing your shape to a massive draconic fish. For every 5 cubic feet of water you absorb through this spell, your size category increases by 1 to a maximum of Gargantuan. If you exit your spirit form, the water from this spell returns to normal water, and you lose all of this spell's effects. While in this form you have the following properties:

• Immunity to bludgeoning, slashing, and piercing damage.
• Vulnerability to lightning and thunder damage.
• Crashing Wave: You can unleash a torrent of water, all creatures within a 10 ft wide 150 ft line must attempt a Dexterity saving throw. On a failure, they take 10d6 bludgeoning damage, and are knocked prone. On a success, they take half as much damage and are knocked prone. The damage increases based on size Huge (10d8), Gargantuan (10d10).
• River of Life: While Gargantuan you may consume 5 cubic feet of water as a bonus action to regain a number of hit points equal to 3d8 + your Constitution modifier.