Being originally a part of the Way of Kensei, the monks of the Way of Mortal Blade sought to use skillful performance of martial arts to give their weapons lives of their own. Monks of this tradition are masters of varying elemental arts, allowing the movement of their weapons to resemble the flowing water, imperishable stone, or heavenly lightning (Inspired by Demon Slayer).

A monk who studied the ways of the mortal blade would never be seen without their weapons, they and the weapon share the same soul. Bystanders that happen to see a mortal blade would be both in awe and terrified, as if they could not tell between the wielder of the blade, and the blade itself. The elemental arts further improved the performance of a mortal blade, each style possessing their own method of besting the opponent in combat. Be it a blindingly swift strike of a spear, or the fluent strokes of a sword, a monk of this tradition would seek the best path to master their elemental arts.

Teachings of the Blade

When you choose this tradition at 3rd level, your devotion to this tradition leads you to master the use of certain weapons, combat styles and stances. You gain the following benefits:

• Mortal Weapons. Choose two types of melee weapons to be your mortal weapons. These weapons can be any melee simple or melee martial weapon that lacks the heavy properties. You gain proficiency with these weapons if you don't already have it. Weapons of the chosen types are monk weapons for you. Many of this tradition's features work only with your mortal weapons.
• Sheathing Stance. You may sheath or stow away your mortal weapon as a bonus action, heightening your senses as you observe your enemies warily. If you did not take the attack action this turn you may use your reaction to impose disadvantage on an incoming melee attack directed towards you. Many of this tradition's features would require you to take this stance before acting.
• Way of Words. You gain proficiency with calligrapher's supplies. 

The Elemental Arts

At 3rd level, after you begin studying your mortal weapons, you also gain the ability to adopt a single elemental art of your choice, bringing the movements of your blade to life by mimicking the chosen element. You will then choose an element and gain the ability to use its different forms. At your option, your mortal weapons gain attributes that reflect the element of your choice. For example, if you decided on the water arts, the blade of your weapons might gain a bluish tint and markings that resembled the white waves.

Flowing Water. This elemental art would guide your attacks with fluid and seamless motions, allowing to strike true no matter how evasive the enemies become. You learn to utilize the first two forms of this fighting style. 

• First Form: Rapid Stream. If you perform an attack with your mortal weapon you may expend 1 ki point to gain advantage on the attack roll, upon hitting you deal extra damage equal to your dexterity modifier.
• Second Form: Windless Ripple. This form counts as a sheathing stance. Upon entering this stance you may expand 1 ki point to enhance your sheathing stance. Instead of a melee attack, you may now use this ability so long as the enemy is within 30 feet of you. If your reaction was not used this way you may gain temporary hit points equal to your proficiency bonus.

Vivid Lightning. This elemental art would empower your attacks with blindingly swift and precise strikes of your weapons, allowing you to cut down your foes in the blink of an eye. You learn to utilize the first two forms of this fighting style.

• First Form: Sudden Flash. You may expend 1 ki point to use 15 feet of your movement to charge forwards in a straight line, this movement would not trigger opportunity attacks and you may charge past a hostile creature. Before, during or after this short dash you may use your action to perform a weapon attack, upon hitting you deal extra damage equal to your dexterity modifier. This form cannot be used if there is not enough space for you to travel.
• Second Form: Gathering Clouds. This form counts as a sheathing stance. Upon entering this stance you may expand 1 ki point to enhance your sheathing stance. Instead of imposing disadvantage, you may make an unarmed strike against the creature. If your reaction was not used this way you may gain advantage on the next attack you make, this effect does not stack.

Tempered Stone. This elemental art would aid you to fortify yourself with defensive techniques then overpower your foes with crushing blows, allowing you to stand up to any challenge no matter how tough the adversary becomes. You learn to utilize the first two forms of this fighting style.

• First Form: Sturdy Blow. If you perform an attack with your mortal weapon you may expend 1 ki point to do extra damage, if the attack hits you deal extra damage equal to your dexterity modifier. In addition, you gain temporary hit points equal to your dexterity modifier until the start of your next turn, you gain this bonus even if you miss the attack.
• Second Form: Living Earth. This form counts as a sheathing stance. Upon entering this stance you may expand 1 ki point to enhance your sheathing stance. Instead of imposing disadvantage and if you are hit, you may roll 1d8 + your dexterity modifier and subtract that much damage from the enemy attack. If your reaction was not used this way, or if you are still damaged you may roll 1d8 + your dexterity modifier and regain that much health at the start of your turn.

 

Study the Ways

At 6th level, you are starting to get familiar with your mortal weapons and your chosen elemental art. You gain the following benefit and learn the third form of your chosen art. 

• Hone the Blade. Your attacks with your mortal weapons count as magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.

Flowing Water. You learn to use the third form of this elemental art, allowing you to maim multiple foes and disturb their actions.

• Third Form: Piercing Rain. When you hit another creature with your mortal weapon, you may expend 1 ki point to cause its next attack to have disadvantage, you also deal extra damage equal to your dexterity modifier. In addition, a chosen creature within 5 feet of your target also takes force damage equal to your dexterity modifier.

Vivid Lightning. You learn to use the third form of this elemental art, you can now damage multiple foes with swift yet deathly strokes of the blade.

• Third Form: Leaping Blaze. When you hit another creature with your mortal weapon, you may expend 1 ki point to cause your attack to deal an extra 1d10 + your dexterity modifier of force damage. In addition, a chosen creature within 5 feet of your target also takes force damage equal to 1d10 + your dexterity modifier.

Tempered Stone. You learn to use the third form of this elemental art, gaining the ability to defend your nearby allies.

• Third Form: Gleaming Summit. When you hit another creature with your mortal weapon, you may expend 1 ki point and gain temporary hit points equal to 1d6 + your dexterity modifier. In addition, a chosen creature within 5 feet of your target receives +2 AC until the start of your next turn. 

 

Diligent Learner

At 11th level, after truly becoming one with your weapons, you are now an advanced user of your chosen elemental art, you gain the following benefit and learn the fourth form of your elemental art. 

• Immortal Weapons. Thanks to your mastery of ki, your mortal weapons cannot break, rust, or be corroded. When you die your weapon(s) turn into salt for Flowing Water, glass for Vivid Lightning, and dust for Tempered Stone.

 Flowing Water. You learn to use the fourth form of this elemental art, giving you the ability to refocus your attention after quickly analyzing the situation.

• Fourth Form: Changing Tides. When you make an ability check, an attack roll, or a saving throw and have disadvantage, you can spend 2 ki points to cancel the disadvantage for that roll.

 Vivid Lightning. You learn to use the fourth form of this elemental art, you now know how to emulate the sound of thunder with a stroke of your weapon, allowing you to damage your enemies even from a distance.

• Fourth Form: Distant Thunder. After spending 2 ki points, the attacks made with a mortal weapon of your choice gains 10 feet of attack range. In addition, your weapon now deals force damage and ignores half cover when the target is not within 5 feet of you. You cause a thunderous boom that is audible out to 100 feet with each attack. This ability lasts for 30 seconds (5 turns).

Tempered Stone. You learn to use the fourth form of this elemental art, in the face of danger you may now rely on your weapon to grant you extra defense.

• Fourth Form: Unbreakable. After you are hit by an attack, and if your hit points are not reduced to 0, you may expend 2 ki points to gain temporary hit points equal to half the amount of damage taken (rounded down) until the end of your next turn. You may use this feature once per short or long rest.

 

Final Form

At 17th level, you become a true master of your mortal weapons and your chosen elemental art. You gain the following benefits and learn the final form of your chosen art.

• Summon Weapons. While in contact with it, you may now turn your mortal weapons into salt, glass or dust (depending on the elemental art you chose) when you desire to. If one or both of your mortal weapons are currently salt, glass or dust, you may spend your bonus action to summon one of the mortal weapons. You cannot summon a weapon to be your third mortal weapon.

 Flowing Water. You learn to use the fifth and final form of this elemental art. With fluent and precise movements of your weapons you can now disturb multiple foes surrounding you both physically and mentally.

• Fifth Form: Silent Waves. You may use your action to expend 3 ki points to cause up to three hostile creatures within 60 feet of you to have disadvantage on all of their attacks, ability checks, and saving throws until the start of your next turn.

 Vivid Lightning. You can now utilize the fifth and final form of this elemental art, granting you the ability to strike at your foes while traveling at a speed only rivaled by light itself.

• Fifth Form: God Speed. Upon spending 4 ki points you may spend up to your movement speed to charge forwards in a straight line, you do not trigger any opportunity attacks. Before, during, or after this movement you may use your action to make your attacks. In addition, during the charge, all other hostile creatures of your choice that are within your mortal weapon’s attack range take damage equal to 1d10 + your dexterity modifier.

Tempered Stone. You now know the fifth and final form of this elemental art. When given the opportunity, you can now drop your defences to deal a single brazen and concentrated attack, crushing your foe with a perfect combination of brute force and skill. 

• Fifth Form: Dust to Dust. When you hit another creature with your mortal weapon, you may expend 4 ki points to deal extra damage equal to your temporary hit points. As a result, you lose all your current temporary hit points. If you do not have temporary hit points, you deal extra damage equal to 4d10 + your dexterity modifier. As a result, the next attack against you would have advantage.