Way of the Abyssal Depths

On the path of enlightenment, many monks find the push and pull of the tides to be a calming sensation, one that mirrors the push and pull of the world. Some monks, however, find that it calls to something deeper, ancient and primal. Perhaps this instinct reveals a truth to their mortal minds - or perhaps it merely brings them one step closer to being preyed upon.

Hadal Tide

When you take this subclass at 3rd level, you gain a swimming speed of 40 feet and can breathe underwater. In addition, the abyss's call resonates with your body; while you are underwater, grappling a creature does not reduce your speed.

Oceanic Armament

Also at 3rd level, you can manifest the sea's wrath in your own flesh. Once per turn, when you make an unarmed strike, you can use one of the following natural weapons.

Claw. You strike with a chitinous claw, dealing slashing damage. Creatures you hit bleed, taking additional slashing damage equal to your Martial Arts die at the start of their next turn.

Tendril. You strike with a gripping tentacle, dealing bludgeoning damage. Creatures you hit are grappled, and at the start of your turn can make a Strength saving throw to be released from your grasp. You can only grapple one creature at a time in this way.

Spine. You strike with a venomous spine, dealing piercing damage. Creatures you hit must make a Constitution saving throw, and are poisoned until the end of your next turn if they fail.

Primordial Current

Starting at 6th level, your connection to the abyss allows you to briefly manifest the abyss's power. At the start of each of your turns, you can cause a tide of spectral seawater to surge out from you in a 10 foot radius sphere. This area is treated as difficult terrain for creatures of your choice and underwater for yourself.

The spectral water fades at the start of your turn.

Liquid Form

The limitations of the flesh no longer hamper your physical form. Starting at 11th level, you can squeeze through a space as narrow as 1 inch wide, dissolving into seafoam to reform elsewhere. In addition, you can move through a space occupied by a creature in this way, but you must end your turn in an unoccupied space.

Charybdis's Call

At 17th level, you can subject your foes to the call of the abyss with your mere presence. As an action, you can choose any number of creatures within 30 feet that can see you. Each target must succeed on a Wisdom saving throw or be charmed by you for one minute. While charmed in this way, a creature can do nothing but use its movement to approach you in a safe manner. If an affected creature moves within 5 feet of you, it takes 8d10 psychic damage, and the effect ends for that creature. Each time an affected target takes damage, it can make a Wisdom saving throw. If it succeeds, the charm ends for that target, and it is immune to this effect for the next 24 hours.

Once you use this feature, you can't use it again until you finish a long rest.