Path of the Depths

Wator Barb go spleesh splosh

Gift of the Drowned Ones

Starting when you choose this path at 3rd level, you gain a swimming speed equal to your walking speed and can now breathe underwater as if on land. If you already have a swimming speed, it is instead increased by 10 feet.

Dredge Line

Also at 3rd level, you manifest an additional appendage when you enter your rage. This appendage can be a large anchor, a kraken tentacle, or preternatural jaws; The appearance you choose does not matter, it is purely aesthetic, and you should work with your DM to determine something that fits your character.

When you take the attack action on your turn, if you are raging you may replace one of the attacks with a strike of your appendage towards a target you can see within 15 feet of you. If the target is of Large or smaller size it must make a Strength saving throw (DC equals 8 + your Proficiency bonus + your Strength modifier) or be pulled up to 10 feet in a straight line towards you. You may use this feature a number of times equal to your Strength modifier (minimum one) per short rest.

Ghostwater Dive

Beginning at 6th level, you can burst into water and then materialize somewhere else. As an action, you magically teleport up to 30 feet to an unoccupied space you can see. Before or after teleporting this way, you may make one attack as part of this action.

Moving this way does not invoke opportunity attacks nor does it count against your movement speed allowed per turn. You may use this ability a number of times equal to your Proficiency bonus per long rest.

Manifestations of the Deep

At 10th level, you can manifest additional adaptations of the deep. Select one of the following manifestations from below. 

• Eyes of the Deep - You become hypersensitive to the environment around you. You have advantage on all perception checks.
• Arms of the Deep - You create an additional appendage as per your Dredge Line feature. When you use this feature, you may replace up to two attacks instead of one, and you may also replace those attacks with grapple attempts.
• Heart of the Deep - As a bonus action on your turn, you may gain a number of temporary hit points equal to 1d12 plus your Barbarian level. You may do this a number of times equal to your Constitution modifier (minimum one) per long rest.
• Soul of the Deep - You have immunity to the charmed and charmed.
• Body of the Deep - Your skin hardens and you gain a +1 bonus to your Armor Class.

Whenever you finish a long rest, you may choose a different manifestation.

Depth Charge

At 14th level, when you use your Ghostwater Dive feature, you now appear with a wave of tidal force. Whenever you re-appear after teleporting via your Ghostwater Dive, all creatures within 10 feet of you must make a Strength saving throw (DC = 8 + your Proficiency bonus + your Strength modifier) or take 6d6 force damage and be knocked prone. On a successful save, a creature takes half this damage and is not knocked prone.