Way of Sendō

The Way of Sendō is one not known by many monasteries, let alone practiced; only 1 in 1,000 know the secrets to the fighting style known as Sendō. The art of Sendō is one that focuses on ripples created through calm and collected breathing, manifesting an ability known as "Hamon", containing powers similar to the energy of the sun. Hamon masters usually use this art to either harm or heal, manifesting as yellow crackles of lightning or a soft multicolored glow, usually around the their arms.

Ripple Rules and Additional Capabilities:

1. The Ripple, also known as Hamon, is a meditative martial art that requires precise and practiced breathing technique. If an effect makes it so you cannot breath, you cannot use the Ripple. However, once you reach level 6 and gain access to Overdrives, you have advantage on any saves against things that prevent you from breathing correctly.
2. When exhausted (Status Condition) it becomes harder to utilize your Ripple to its full potential. For each point of exhaustion, your Ripple deals -2 damage, bottoming out at 1 damage.
3. When being revived/resurrected after a Deep Pass Overdrive the attempt will fail unless the target of your Overdrive returns the life energy you gave them.

Hamon

Upon choosing this Monastic Tradition at 3rd level, whether a master has taught you, a stranger jabbed their little finger in your diaphragm, or it began to manifest, you gain access to the mystical ability known as "Hamon." Minor uses for Hamon could be holding a liquid within an upside down container, hardening dead leaves to the toughness of cloth, or healing minor cuts. However, to use it to its fullest potential requires courage, steady breathing, and ki. As a bonus action, you can spend 1 ki point to infuse your unarmed strikes or any conductive object with Hamon for a number of rounds equal to your Wisdom modifier (minimum of 1). Whenever you attack, you deal additional damage equal to your Martial Arts die roll. This damage counts as radiant damage. You can spend additional ki points for additional damage dice.

These are some items that are conductive to Hamon:

• Living creatures (human, elf, dwarf, animals, etc.)
• Organic material (organs, hair, plants, cloth, etc.)
• Liquids (water, oil, blood, etc.)

While you can use Hamon, there are certain rules when it comes to using it. If you cannot breathe properly, you can't use any of these features. While inflicted with the grappled condition, you would treat as if you could not breathe. While frightened, you cannot control your breathing properly, as it is erratic. 

Additionally as an action, you can spend 1 ki point to heal another creature that you can touch. The amount of hit points healed is equal to your Martial Arts die roll. You can spend additional ki points for additional healing dice.

Zoom Punch

Beginning at level 3, by dislodging your joints and artificially stretching your muscles with the ripple, your attack range with unarmed strikes and weapons increases to 10 feet. Requires 1 Ki point. At level 11 you can do a Overdrive and Zoom Punch together if you spend the necessary Ki Points for the Overdrive. This does not work with Flurry of Blows or Sunlight Yellow Overdrive.

Ripple Hypnosis

Beginning at level 3, similar to the Charm Person spell, you can use Ripple hypnosis to charm a target who must make a Wisdom saving throw, and does so with advantage if you or your allies are fighting it. The Save DC for this is 8 + your Wisdom modifier + your Proficiency Bonus. On failure, the target is charmed and regards you as a friend per Charm Person rules. If they succeeded, the effect does not take hold. Requires 1 Ki point and the target must be touched by your Ripple for this to take effect. Ripple Hypnosis does not work on any undead.

Ripple Cutter

Beginning at level 3, you can infuse your Ripple into liquids you drink and make them into deadly disks you can fire at your opponent. As a bonus action, the disks can deal 2d6 + Proficiency Bonus radiant damage to non undead or 2d10 + Proficiency Bonus to undead. This ability has a range of 30 feet and requires 1 Ki Point and liquid to shoot.

Walk on Water/Cling To Surface

Beginning at level 3, the beat of your Ripple is steady and strong. As a bonus action, by allowing your Ripple to go through your feet into liquid, you can now walk on water for 1 minute per Ki point spent. At 3 Ki points spent, you can bring one ally with you as you walk over the water. You can also add +5 to any climb check on a watery/oiled/slippery surface by spending 1 Ki point and climbing with your fingertips.

Overdrive

Beginning at 6th level, you can use the following Overdrives:

• Sendō Hamon Overdrive: As a bonus action, you may strike an object the target is touching within 30 feet, dealing damage equal to one unarmed strike.

• Scarlet Overdrive: Your Hamon glows a brilliant red and crackles like an intense flame. As a bonus action, you may spend 3 ki points to coat your arm(s) and create scarlet Hamon. Your next unarmed attack deals an additional 3d4 fire damage plus your Wisdom Modifier. You can spend additional ki points for additional d4s. Any flammable objects that are struck with this attack immediately catch on fire.

• Turquoise Blue Overdrive: Your Hamon glows a brilliant blue and roars like an incredible tempest. As an action, you may spend 3 ki points to create turquoise Hamon and make a ranged attack that equals your Martial Arts die and 3d4 force damage plus your Wisdom modifier. If the attack hits, the enemy is pushed back 10 feet. You can spend additional ki points for additional d4s and push the enemy back 5 feet farther.

• Metal Silver Overdrive: You conduct your Hamon to anything that seems metal and crackles with a silver shine. As a bonus action, you may spend 3 ki points to infuse whatever weapon you hold with Hamon. Your next Attack with that weapon deals an additional 3d4 radiant damage. You can spend additional ki points for additional damage die

• Sunlight Yellow Overdrive: Your Hamon shines a golden yellow, as bright as the sun itself. As an action, you may spend 4 ki points to make a devastating Attack, rolling 8 Martial Arts dice, the first 4 being regular unarmed attacks and the other 4 being used for radiant damage. You must take a short or long rest before using this Overdrive again.

• Tornado Overdrive: You leap into the air and perform a spinning dive kick on one enemy within 60 ft. As an action, you may spend 3 ki points to roll at disadvantage on this attack, and do 4 Martial Arts Die + your Dexterity modifier damage on a hit. In addition, your opponent in knocked prone if they are Medium or Smaller.

• Earthquake Overdrive: You make a series of strikes targeting your opponents vitals. As an action, you may spend 3 ki points to deal only 2 Martial Arts Die damage, but crit on a 15+ roll to hit.

Forced Breathing

Beginning at 11th level, you learn to pinpoint vital organs in a creature's respiratory system. As an action, you may spend 4 ki points to make an unarmed attack against a creature. The targeted creature must make a Constitution saving throw to contest your ki save DC. If it is successful, they simply take the rolled damage. If it fails, the creature takes damage and loses its breath, inflicted with the stunned condition until the end of your next turn.

However, if you spend 4 ki points to perform this action on a willing creature, they also have to make a Constitution saving throw to beat your ki save DC. If it fails, they take the damage rolled and are afflicted with the stunned condition. However, if it is successful, they temporarily have access to the Hamon feature for a number of rounds equal to your Wisdom modifier. They can perform the same actions and bonus actions as if they have the feature, with a reserve of points they can use equal to their Wisdom modifier (minimum of 1).

Fighting Spirit

• At 11th level you unlock your potential as a Hamon Monk. Choose one fighting spirit:

Fighting Spirit: Battle Tendency

Rather than rely on the strength of your ripple, you instead rely on your cleverness as a fighter to get you through the day. You gain the Feat Trickster Tactician, which gives you proficiency in Sleight of Hand (Dexterity) checks, Insight (Wisdom) Checks, and a +1 increase to your Intelligence score.

Fighting Spirit: Diamond is Unbreakable

The compassion you feel for your friends and allies as well as your need to protect people grants you the Feat Crazy Diamond, which allows you to cast Cure Wounds at a max of level 2 for 1 Ki point, and cast Revivify once per long rest for 2 Ki points.

Fighting Spirit: Phantom Blood

Your burning hatred for undead and powerful ripple manifests. You gain the Feat Luck and Pluck, allowing you to reroll a d20 and change an attack roll, a saving throw, or an ability check twice per long rest and gives proficiency with the longsword and greatsword.

Fighting Spirit: Stardust Crusader

You are, without a doubt, the coolest badass to ever walk the earth. This edgy coolness grants you the Feat OraOraOra, which gives you two more attacks during a Flurry of Blows. If both land, the enemy takes an extra 1d4 bludgeoning damage. OraOraOra can only be used twice per long rest.

Fighting Spirit: Stone Ocean

Your rough attitude gives rise to the Feat Stone Free. This Feat gives you proficiency in Medicine (Wisdom) checks, a +5 to perception checks that rely on hearing, and the ability Twisted Fist which allows you to, three times per day, deal an extra 1d6 bludgeoning damage on a punch or Overdrive.

Fighting Spirit: Vento Aureo

Due to your darker path than most Ripple Monks, you you gain the Feat Gold Experience, giving you the ability to turn your Ripple Overdrive damage into necrotic rather than radiant, and you gain the ability Life Shot. As a Bonus Action, Life Shot can be targeted on others beside yourself and gives a temporary (1 minute) +2 to all Intelligence checks and saving throws for 3 Ki points. Your Ripple now deals undead damage as specified to non-undead and deals none to undead.

Deep Pass Overdrive

At 17th level, you master the final technique of Hamon: the Deep Pass Overdrive, using it to transfer some of your own life energy into others. As an action, you may spend 5 Ki points to heal a creature a number of 5 monk Hit Dice rolled. However, you take the number rolled as damage and age by 5 years. You may spend additional Ki points for each additional Hit Die. For every additional Ki point you spend, you age by an additional 5 years. You regain use of this feature after a long rest.

But, you may choose to expend all of your ki points and die to permanently give the target creature the following:

• 3 monk Hit Dice

• Access to the Hamon and Overdrive features

• A pool of Ki points equal to the creature's Wisdom modifier (minimum of 1) that can be regained after a short or long rest.