bottomless domain

your worth ship the gods of the ocean and it's infinite, never ending potential.

Soul Of Water

due to your worship of deity's of the endless power of water you no longer need to breath, or drink.

in addition to this you gain a swimming speed equal to your walking speed

Step of the ocean

Your worship of the gods of a place you are not accustomed to has allowed you to treat it as your own.
Starting at first level you can walk on liquid as if it was a solid surface.

Channel Divinity: Ice Tomb

Starting at second level you can expend one use of your channel divinity to use ice tomb,
As an action point choose up to 4 creatures within 120ft 
these creatures must make a strength saving throw or be stunned by ice,
creatures stunned in this way can attempt to make a strength saving throw DC equal to your spell save DC+ proficiency bonus 
any creature that fails this save takes 2d10 cold damage per failed save
a creature must succeed the save to escape 
this prison lasts for 1 minute.

on a successful save the creature is no longer restrained.

Liquidous limbs

at 6th level as an action you may elongate liquidous arms for 1 minute whilst in said form you gain the following benefits,

you gain either an extra pair of legs, an extra pair of arms or a pair of wings.

 

arms

you gain 2 extra hands and arms with this hands and arms that you can:

hold weapons with, perform the somatic components of spells whilst all your hands are bound, and use objects with as a bonus action, you can free yourself from non magical restraints by expending half your movement.

legs

you gain an extra pair of legs made of liquid you gain the following benefits,

you ignore non magical difficult terrain and magical difficult terrain if it is created by the ground,
you gain a climbing speed equal to your walking speed and can leave your hands free whilst climbing on walls and ceilings, 
you gain the benefits of the jump spell permanently,
your speed increases by 10ft. (any speed including flying)

wings

you gain wings made of water, you gain the following benefits;

you gain a flying speed equal to your walking speed, however you cannot move upwards with this flying speed however you can still flap your wings as a bonus action to move 10ft up.

Divine strike

At 8th level, you gain the ability to infuse your weapon strikes with divine energy. Once on each of your turns when you hit a creature with a weapon attack, you can cause the attack to deal an extra 1d8 bludgeoning damage to the target. When you reach 14th level, the extra damage increases to 2d8.

(this damage is treated as magical)

saint of the abyss and waves

starting at 17th you gain the benefits of all 3 extra body parts 
additionally you can cast the spell plane shift targeting you and one other creature, to the plane of water only, requiring no material components