Revised Way of Four Elements

Four elements but good be your inner avatar 

Elemental Martial Augmentation

When you reach 3rd level, choose one of the following features to gain: 

Fangs of the Fire Snake

As a bonus action, you may expend 1 ki point to summon fiery whips that extend from your wrists and ankles for one minute. During this time, your reach with your unarmed strikes increases to 10 feet, they deal fire damage instead of bludgeoning, and when you hit with an attack, you can use 1 ki point to roll a martial arts die and add it to it’s damage.

Fists of Unbroken Air

When you make an attack roll against a creature you can spend 1-3 ki points forcing the creature to make a strength saving throw against your ki saving throw. On a failed save, the creature takes bludgeoning damage equal to an amount of martial arts die equal to the ki points you spent and is knocked prone.  If the creature hits a wall during this 20 feet of movement they take an additional 2d6 bludgeoning. On a successful save, the creature takes half as much damage, and isn't knock prone. For the next minute the monk's hands are covered in rapid moving hot and cold air. During this duration when you hit a creature it must make a dexterity saving throw or be knocked prone.

Skin of Hardened Rock

As a bonus action you may use 1 ki point to coalesce a hard layer of rock around your body increasing your AC by half of one roll of your martial arts die. When you hit a creature they take extra damage equal to your proficiency bonus; this can only be applied once per turn.

Water Whip

As an action on your turn you can expand 2 ki points to create a whip of water that lasts for one minute and can be used to unbalance a foe. You are proficient with the whip and it uses your dexterity modifier for attack and damage roles. After forming the whip you may make an attack against a creature within 15 feet of you using the whip as part of the same action. This attack deals bludgeoning damage equal to three rolls of your martial arts die, if the creature is hit by the attack it has to succeed a dexterity saving throw if it fails it is either knocked prone or thrown 15 feet in any direction. On a successful save, the creature isn’t knocked prone or moved. While the whip is out you can replace one of your attacks with an attack from the whip using the same effects as stated above.

Elemental Blessings

At 6th level, your study of the elements has altered your physical features, granting you enhanced attributes. You gain one of the following features of your choice:

Earth

Anytime you take damage you can reduce the damage taken by an amount equal to one roll of your martial arts die.

Fire

You gain resistance to fire damage and can spend 4 ki points to gain immunity to fire damage for 10 minutes as a reaction.

Water

You have advantage on saving throws against being knocked prone or moved against your will.

Wind

Whenever you take the dodge action on your turn, you gain resistance to bludgeoning, piercing, and slashing damage until the start of your next turn.

Elemental Incarnation

By 11th level, you’ve learned to channel your ki in order to augment your being, transforming you into the raging elements you study. Spend 6 ki points to enter your chosen transformation for one minute. You gain one of the following features of your choice:

Earth

You gain a burrowing speed equal to your walking speed and you travel through earth without upheaving any dirt or rock. When you hit a creature you can force them to make a strength saving throw against your ki saving throw and on a failed save; they are restrained as rock-like chains hold them down and can’t take reactions until they are not restrained. Creatures can repeat this saving throw at the end of each of they turns or another creature can attack and try to break the chains(AC: 15 HP: 10).

Fire

You can fit in any space that is 1 inch by 1 inch. Any hostile creatures within 15 feet of you take one roll of your martial arts die at the start of their turn. When a creature moves within 15 feet of you as a reaction you can let out a blinding pulse forcing all creatures with 15 feet of you to make a constitution saving throw or be blinded.

Water

The area within 15 feet of you in difficult terrain and every 5 feet a creature travels within this difficult terrain they must succeed on a dexterity saving throw on a failed save they are knocked prone. When you hit a creature you can push the creature 15 feet away from you.

Wind

You gain a flying speed equal to your walking speed and all attacks against you have disadvantage and when you take bludgeoning, piercing, or slashing damage you can use your reaction to become immune to that instance of one of those damage types.

Unbalanced Harmony

Upon reaching 17th level your monk is so keen on the elemental teachings they can invoke multiple at the same time. When you spend ki points to activate a feature you gained at 3rd or 11th you can spend the ki points for one feature but gain the effects of both.