Path of the Deep One

You am become shark, destroyer of carts.

Deep Adaptation

You gain a swim speed equal to your walking speed and can breathe water and air. Also, when you rage, you gain resistance to cold damage in addition to your normal resistances.

Jaws

You gain a natural weapon in the form of a bite attack. This attack deals piercing damage equal to 1d6 + your Strength modifier. Whenever you make a successful bite attack against a living target, you heal a number of hit points equal to your constitution modifier.

This damage increases to 1d8 at 10th level, 1d10 at 14th level, and 1d12 at 18th level.

Blood in the Water

You gain advantage on your first attack per turn made against a creature with less than its maximum hit points. You also gain blind sense to a range of 15 feet, but can only detect creatures with less than their maximum number of hit points.

At 18th level, the range increases to 30 feet.

Shiver

You gain the ability to cast water breathing, but only as a ritual. Starting at 14th level, all creatures affected by this special casting of water breathing gain a natural weapon in the form of a bite attack. This attack deals magical piercing damage equal to 1d6 + the creature's Strength modifier.

Also starting at 10th level, your bite attack becomes magical for the purposes of overcoming damage resistances and immunity.

Feeding Frenzy

While raging can use a bonus action to enter a feeding frenzy. During this heightened rage, you can use your action to make a bite attack against any number of creatures within 5 feet of you, with a separate attack roll for each target. You can use this feature a number of times equal to your Constitution modifier. You regain all uses of this feature on a Long Rest.

At 18th level, when you enter a feeding frenzy, all creatures affected by your special casting of Water Breathing gain access to your Blood in the Water feature for the duration of your rage.