Base Class: Barbarian
There is something binding you to the abyssal depths of Shadowsea and it's terrible master, Dagon. You may have been a victim of a cult ritual, a chosen servant, or perhaps even the unfortunate progeny of Father Dagon himself... Though you are not without some remains of your own will, it falls to you alone whether you will sink or swim.
Spawn of the Depths
Starting when you choose this path at 3rd level, you gain a swim speed equal to your walking speed and can breathe water and air. You also gain dark vision within 60 feet while you are underwater. If you already have a swim speed upon gaining this feature, it increases by 10 feet. If you have dark vision upon gaining this feature, its range becomes 120 feet while you are underwater.
Riptide
When you enter a rage, the area within 30 feet of you becomes difficult terrain for hostile creatures . Any hostile creature that enters the area for the first time on a turn or starts its turn there must make a wisdom save or become frightened of you until the start of it's next turn. (DC equal to 8 + your Constitution modifier + your proficiency bonus)
Obyrith endurance
When a creature within the area of your Riptide feature deals damage to you, you may use your reaction to gain temporary hp equal to the damage you take, the amount of Temp HP gained this way cannot exceed your constitution ability score. This feature may be used a number of times equal to your proficiency bonus per long rest.
Whelm
When a creature leaves the area of your riptide feature, as a reaction you may move to an adjacent space to that creature at the end of their movement and make an attack of opportunity, you may makes this attack at advantage if the target is currently frightened.
Additionally any other creatures of your choice that are large or smaller within the area of your riptide feature must make a strength saving throw or be pulled with you as you move and knocked prone.
You may use this feature once per short or long rest.
Scent of Blood
When entering rage, you may choose to enter an enhanced rage that provides your riptide feature with additional bonuses. The area of riptide becomes obscured by magical darkness, which you can see through for the duration of this rage. The area of riptide is now treated as underwater for the duration of this rage.
during this enhanced rage when you strike a creature with a critical hit within the area of riptide, abyssal creatures manifest briefly to attack a creature of your choice within the area of riptide. Make a melee weapon attack using your strength and proficiency, this attack deals 2d8 + strength mod and benefits from your rage damage bonus, you regain hp equal to damage dealt by this attack.
This feature may be used once per long rest.