Deep Sea Domain

The Deep Sea domain focuses on the powers at play that maintain life in the deep sea below.Gods of the deep sea have command over the great monsters that reside within their waters, and they imbue their clerics with the monstrous powers. In turn, the duty of clerics of this domain is to maintain respect for life both above and below the surface, as well as ensure the safety and purity of the seas. As such, these clerics often serve as protectors for endangered sea animals or enforcers that punish vessels who don't honor the waters. Gods that hold power over this domain include Umberlee, Istishia, Valkur, and Yeathan.

Deep Sea Creature

When you choose this domain at 1st level, your body itself becomes a vessel of the divine power of your watery deity. You have an unarmored AC equal to 10 + your Dexterity Modifier + your Wisdom modifier, you have a swim speed equal to your walk speed, and can breathe underwater. You can gain the benefits of your unarmored AC with a shield equipped. Your creature type is now monstrosity.

Domain Spells

You gain domain spells at the cleric levels listed in the Deep Sea Domain Spells table. See the Divine Domain class feature for how domain spells work.

Deep Sea Domain Spells

Cleric level	Spells
1st	earth tremor, create or destroy water
3rd	air bubble, phantasmal force
5th	erupting earth, wall of water
7th	black tentacles, control water
9th	destructive wave, enervation

 

Hunger of the Deep

Also starting at 1st level, the innate hunger of the deep causes you to lash out at your enemies. You learn the Primal Savagery cantrip. When you cast it, creatures you hit with it must make a constitution saving throw. On a failure, they have disadvantage on the next attack roll they make before the start of your next turn, as your monstrous hunger rends off a part of their soul.

Channel Divinity: Grasp of the Sea

Starting at 2nd level, you can use your Channel Divinity to summon divine appendages to seize hold of other creatures.

As an action, you can summon spectral tentacles around you. When you do so, all terrain in a 30ft radius of you becomes difficult terrain. As an action, you can force a creature within the difficult terrain to make a strength saving throw. On a failure, they become grappled by the tentacles. At the start of their turn, they can make another strength saving throw. On a success, they break free from the grapple. This effect lasts for 1 minute, or until you are incapacitated.

Channel Divinity: Titanic Expansion

Starting at 6th level, you can use your channel divinity to cause your body grow with the might of sea monsters. As a bonus action, you magically gain the following benefits for 1 minute:

• If you are smaller than large, you along with anything you are wearing and have equipped are large. 
• If your wisdom score is higher than your strength score, then your strength score is temporarily set to your wisdom score.
• You have advantage on strength checks and strength saving throws.
• As part of the action that you activate this ability and as a bonus action on subsequent turns, you can channel the forces of the deep sea into the ground around you. When you do so,  all hostile creatures within 15ft of you must make a dexterity saving throw.  A creature that fails their saving throw takes bludgeoning damage equal to your wisdom modifier(minimum 1) and falls prone.

Potent Spellcasting

Starting at 8th level, you add your Wisdom modifier to the damage you deal with any cleric cantrip.

Formless Horrors

Starting at 17th level, the horrifying truths within your body can horrify other creatures. Once per round, when you force a creature to make a saving throw while you have a Channel Divinity active, you can force a creature within 30ft of you to make a wisdom saving throw(no action required). On a failure, it takes psychic damage equal to your wisdom modifier and becomes frightened of you for 1 hour, as you reveal the indescribable horror of the monsters imbued within you. Creatures who fail this saving throw can make an additional wisdom saving throw at the end of their turn, ending the effect on a success. On a successful save, creatures are immune to this effect for 24 hours. Creatures with a swim speed make this saving throw with advantage.