Monks of the Way of the Riptide seek to channel the duality of water. Water can nurture life and nourish the soul, but can also bring swift devastation. As a tranquil bay can hide a deadly current, so too can these monks drown their opponent in a deluge of blows at a moment’s notice. While they make fearsome warriors, their coastal monasteries are the sites of many an ocean rescue, recovering sailors less attuned to the capriciousness of the sea.

Flowing Soul

Starting at 3rd level, you embody the spiritual tranquility of calm waters. You're at home in water, and you can soothe the injured.

You gain a swimming speed equal to your walking speed, can breathe underwater, and gain the Shape Water and Spare the Dying cantrips.

Surging Strikes

Starting at 3rd level, you learn to imbue your strikes with the swiftness and ferocity of the tempestuous ocean.

If you travel 15ft in a straight line uninterrupted during your turn, you become surging. You can only become surging in this way once per turn.

Surging: The next time you hit with an unarmed strike, it deals additional damage equal to one roll of your martial arts die.

Surging ends when you deal this damage, or when your turn ends.

Additionally, you can choose to deal cold or thunder damage with any of your Unarmed Strikes.

Undertow

Starting at 6th level, you can navigate mystical currents to whisk yourself across the battlefield, leaving turbulence in your wake.

You can use a bonus action to teleport to an unoccupied space that you can see up to 30ft away, and become Surging. The chosen space must be on a surface or in a liquid that can support you without having to squeeze.

When you teleport, you can create a watery vortex at your destination, or the space you teleported from (your choice.) Enemies within 5ft of the vortex when you teleport must make a Strength saving throw. On a failure, they are magically restrained by the vortex until the start of your next turn, at which point it disappears.

You can use this feature a number of times equal to your proficiency bonus, and regain all uses on a Short Rest.

Tranquil Veil

Starting at 11th level, you can summon a soothing veil of water around you to dampen the harms you suffer.

As a reaction immediately after taking damage, you can grant yourself temporary hit points equal to half the damage taken. These temporary hit points last for 1 minute.

You can use this feature a number of times equal to your Wisdom modifier (minimum of 1), regaining all uses on a Long Rest.

Thallasic Arbiter

Starting at 17th level, you may invoke an aura of the fathomless depths, summoning a watery arena in which you mete out the ocean's fury.

You can use your action to conjure a swirling mass of 5-foot-deep water in a 30-foot radius, centered on you for 1 minute. You may choose any number of creatures to be immune to its effects. While this area is in effect, the following effects apply:

The area is difficult terrain.

A creature that starts its turn in the area is subjected to a Riptide.

You may use your action and spend 1 ki point to subject any creatures of your choice in the area to a Riptide.

You automatically become Surging at the start of each of your turns.

When you take this action, affected creatures within the area are subjected to a Riptide. The effect ends if you are incapacitated, airborne at the end of your turn, or if you dismiss it (can be done freely.)

If you are submerged in water, the area of this effect is a 30ft-radius sphere instead.

Riptide: The creature must make a Strength saving throw against your Ki Save DC. On a failure, the creature takes 6d6 bludgeoning damage and is pulled 15 feet toward you.

Once you use this feature, you cannot use it again until you complete a long rest.