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Monks that follow this tradition, unlike other element weilding traditions, focus in developing a more profound connection with a single element: fire, air, water, or earth. A monk normally chooses the element most aligned with their personality, for example an airbender tends to be lighthearted and carefreee, while firebender can be passionate and hotheaded, an earthbender may act stoic and rough, or a waterbender be calm and easygoing.

The different techniques needed to manipulate a certain element using your ki or "bending" it result in individual combat styles for each element. Firebending is offensive, attacking head on with exploding blazes of fire: airbending is evasive, dodging and finding the best position to then attack with powerful blasts of wind: waterbending is flexible, flowing from defense to offense and attacking with the most appropriate form of water each time: earthbending is defensive, waiting for the perfect moment to overwhelm your target with big chunks or sharp spikes of rock.

A monk of this tradition must learn that its element is not a mere weapon, but an extension of its body, and can be a source of wisdom both in combat and outside of it. 

Bending Arts

When you choose this tradition at 3rd level, you spiritually connect with one of the four elements and learn to manipulate its form or "bend" it, using the energy within you, becoming a part of your martial arts style.

You gain a new attack option that you use with the Attack action, a Bending Strike. This special attack is a melee weapon attack (even though your element is not a weapon) with a range of 10 feet. You are profiecient with it, and you add your Dexterity modifier to its attack and damage rolls. Its damage die is a d4. This die changes as you gain monk levels, as shown in the Martial Arts column of the  Monk table. 

When you take the Attack action on your turn and use a Bending Strike as part of it, you can make one Bending Strike as a bonus action. You can also spend 1 ki point to make a Bending Strike twice as a bonus action. Choose between fire, air, water and each feature of the tradition as you level up.

Airbending

Your Bending Strike deals bludgeoning damage. If this attack hits a creature no more than one size larger than you, you can deal the damage and try to push it 5 feet in a direction you choose unless it succeeds on a Strength saving throw. Instead, you can forgo the damage of the attack to knock prone the target unless it succeeds on a Strength saving throw.

Earthbending

Your Bending Strike deals bludgeoning or piercing damage. You can also make ranged Bending Strikes with a normal range of 20 feet and a long range of 60 feet.

Firebending

Your Bending Strike deals fire damage. When you are directly under the sun, you can harness its energy to add half your Wisdom modifier (rounded up) to the damage of your Bending Strikes.

Waterbending

Your Bending Strike deals your choice of bludgeoning, slashing, piercing or cold damage. While you are directly under the moon, you can harness its energy to add half your Wisdom modifier (rounded up) to the damage of your Bending Strike.

Shape of the Elements

Also at 3rd level, as part of your bending, you can mold your element in more subtle manners. As an action you can manipulate your chosen element if it is within 15 feet of you in one of the following ways:

• Cause up to a 5-foot cube of your element to shape itself into a crude form you designate or move to a place within range. This movement does not involve enough force to cause damage.
• Transform the physical properties of up to a 5-foot cube of your element, such as lighting or snuffing out a small fire, freezing water or creating mist, or turning sand into sandstone.
• Create a harmless, instantaneous sensory effect related to your element, such as a shower of sparks, a puff of wind, a spray of light mist, or a gentle rumbling of stone.

Wisdom of the Elements

When you reach 6th level, you ascertain the less apparent attribudes of your element and develop techniques that imitate them:

You have a number of uses of this feature equal to your Wisdom modifier, and you regain all expended uses when you finish as long rest. While you have no uses left, you can spend 1 ki point to use this feature again.

Circle Walking (Air)

You ignore difficult terrain when you Dash.

Also, when a creature misses you with a melee attack roll, you can use your reaction to spend a use of this feature and move up to half your speed without provoking opportunity attacks. If you do not leave the attack range of the creature, you have advantage on the first attack you make against it on your next turn.

Energy Conduit (Fire)

You have resistance to cold damage, and you do not suffer the negative effects of extreme temperatures.

Also, when you suffer fire or lightning damage, you can use your reaction to spend a use of this feature and gain resistance to the triggering damage type until the beginning of your next turn. As part of this reaction, you can spend 1 ki point to make a Firebending Strike against a creature you can see withing range, dealing fire or lightning damage, the same type as the triggering damage.

Flowing Paths (Water)

You gain a swimming speed equal to your walking speed.

You can spend a use of this feature and focus for 10 minutes redirecting the ki pathways in the body of a creature, within 5 feet of you, to aid its natural healing. The creature can spend any number of their Hit Dice and regain hit points equal to the total rolled plus half your monk level.

Seismic Sense (Earth)

You have advantage on saving throws against falling prone.

You can spend a use of this feature as a bonus action to gain tremorsense with a range of 60 feet for 1 minute. Using this way if feeling, you can interpret the vibrations of a boby as long as it is touching the ground, granting you advantage on Wisdom (Insight) checks on any creature within your tremorsense.

Bending Arts Improvement

At 6th level, the damage of your Bending Strikes counts as magical for the purpose of overcoming resistances and immunity to nonmagical attacks and damage.

Ki-Empowered Bending

Beginning at 11th level, you can instill ki in your chosen element to create more powerful bending moves. As an action, you can spend 1 ki point to make one of the following techniques:

• Bending stream. Each creature in a line 30 feet long and 5 feet wide emanating from you in a direction you choose must make a Dexterity saving throw. On a failed save, a creature takes damage of the same type as your Bending Strikes equal to three rolls of your Martial Arts die, or half as much damage on a success.
• Bending wave. Each creature is a 10-foot radius sphere centred on you must make a Dexterity saving throw. On a failed save, a creature takes damage of the same type as your Bending Strikes equal to two rolls of your Martial Arts die, or half as much damage on a success.

You can increase the damage of this techniques by spending extra ki points. Each point you spend increases the damage of the attack by one roll of your Martial Arts die. The maximum number of ki points (1 plus any addition points) that you can spend equals your proficiency bonus.

Additionally, you can add an extra effect to the attack depending on your chosen element:

Exploding Tremors

Ground in the area of your Bending Stream and Bending Wave becomes difficult terrain until cleared.

Forceful Torrents

A creature that fails the saving throw against Bending Stream or Bending Wave is knocked prone.

Raging Gales

A creature that fails the saving throw against Bending Stream or Bending Wave is pushed 10 feet away from you.

Searing Flames

A creature that fails the saving throw takes extra fire damage equal to your Wisdom modifier..

Master Technique

When you reach 17th level, you reach the peak of your bending abilities, becoming a master of the element. Choose a master technique from your element to specialize on:

Mastery of Air - Become Wind

By leaving all earthly attachments, you have found true freedom. You gain a flying speed equal to your movement speed, and while flying you gain the same benefits as if under the freedom of movement spell.

You can also detach your spirit from your body through meditation. You can spend 5 ki points to cast project image without providing any material components. When you cast it this way, your image looks translucent and spirit-like.

Mastery of Air - Steal Breath

You reject the traditional philosophy of airbending, learning a technique that steals your opponent's breath. You can spend 5 ki points as an action to concentrate (as if you were concentrating on a spell) and extract the air of a creature you can see within 30 feet of you. The creature runs out of breath and begins suffocating (see the rules for suffocating in Chapter 8 of Basic Rules). While suffocating, at the begining of its turn the creature must succeed on a Constitution saving throw or be stunned until the begining of its next turn.

You must use your bonus action on subsequent turns to maintain this effect, and it ends early if you lose your concentration or if the creature moves further than 30 feet from you.

Mastery of Earth - Lava-bending

You learn to instill energy in the rocks you bend, heating them to a point where they melt. When you make a Ki-Empowered Bending attack, you can choose to melt the ground, dealing 2d10 extra fire damage with the attack and flooding the ground with lava for 1 minute or until you use an action to end the effect. During that time, ground in the area is considered difficult terrain, and a creature that enters the area for the first time on a turn or starts its turn there must make a Dexterity saving throw and suffer 8d10 fire damage on a failure, or half as much on a success. 

Once you use this feature, you cannot use it agains until you finish a short or long rest, unless you use 4 ki points to use it again. 

Mastery of Earth - Metal-bending

You are capable of bending the small particles of earth that remain even in most refined metals. Any feature in this tradition that refers to your element can be also applied to any metal, and you can choose to give yourself advantage or impose disadvantage on any skill check that uses your metal-bending, such as when trying to disarm a creature holding a sword or pushing an armored creature.

Additionally, you add half your Wisdom modifier (rounded up) to the attack and damage rolls of your Earthbending Strikes against creatures wearing metal armor, and you deal double damage to creatures, objects and structures made of earth or metal.

Mastery of Fire - Lightning-bending

You learn to remain cool-headed even in the raging flames of combat. You can use Stillness of Mind as a bonus action. In complete absence of emotion, you are able to separate the positive and negative energies of fire. When they collide again, lightning is generated. When you make a Bending Stream attack, you can create a lightining bolt, dealing lightning damage instead of fire damage, and for every creature that fails the saving throw, you can spend 1 ki point to cause it to be stunned, until the end of your next turn.

Mastery of Fire - Sun-bending

You understand the true nature of fire, not just as a destructive force, but as the source of all life and energy. You can spend 3 ki points to cast remove curse and 5 ki points to cast greater restoration without providing any material components. Also, when you deal fire damage, you ignore a creature's resistance to it, and creatures immune to fire damage become resistant for you instead.

Mastery of Water - Blood-bending

You learn the ability of controlling the water inside a creature. You can use an action to concentrate (as if you were concentrating on a spell) and try to seize control of a creature you can see within 30 feet of you. You spend a number of ki points: 2 if the creature is Medium or smaller, 4 if it is Large, or 6 if it is Huge or bigger. The creature must then make a Strength saving throw or be paralyzed. A creature that has no water on its body automatically succeeds in the saving throw. At the end of each of its turns the target can make another Strength saving throw (despite being paralyzed), ending the effect on itself on a success. While paralyzed in this way, you can use your action to move a creature up to 15 feet, provided it does not leave your range.

You must use your bonus action in subsequent turns to maintain this effect, up to 1 minute, and it ends early if you lose your concentration or if the creature moves further than 30 feet from you.

Mastery of Water - Spirit-bending

Using advanced healing techniques, you can soothe and restore the energy paths that flow through a creature connecting its body and spirit. You can spend 3 ki points to cast calm emotions, and when you cast it this way you can only choose one target within 30 feet of you, affecting any type of creature, not only humanoids. You must use your bonus action on subsequent turns to maintain this effect, and it ends early if the creature moves further than 30 feet from you.

If you concentrate for the full duration of the spell, the effect lasts for 1 hour and, if the target is native to a different plane of existence than the one you are on, it is banished as if under the effects of the banishment spell.

Finally, you can spend 4 ki points to cast revivify without providing any meterial components, and you cannot cast it again this way until you finish a long rest.