Base Class: Monk
Mastery of the Elements is not for the feint of heart. Having to endure the various dangers of the Primordial Soup is foolish for any who doesn't have their wits about them. But once mastered the Primordial power is not one to be scoffed at.
Blessings of the Elements
When you take this subclass at third level you gain the following benefits.
Fists of Fire. When you use furry of blows you can expend an extra ki points to wreath your fists with fire. The attacks deal extra fire damage equal to one roll of your monk die.
Unmoving Stance. When you take the dodge action either as an action or with your patient defense you can use a ki point to make yourself unmovable by magic or other means. You cannot be knocked prone. Additionally any creature that tries to move you must make a strength save vs your monk dc or have 0 feet of movement until the start of your next turn.
Wings of the Wind. When you use step of the wind you can use an extra ki point to gain a flying speed until the end of your turn. If your not on the ground you fall as per normal.
Shield of Water. When an attack is made against you and it hits you can use a reaction to form a shield of water between you and the attack. You can spend any number of ki points. For each ki point spent roll a martial arts die and reduce the damage by the number rolled.
Emulation of the Elements
Emulation of the Elements. At Six Level you gain the ability to use unique attack stances to increase your elemental affinity. As an Action you can take one of the following stances or for 2 ki points you can enter a stance as a bonus action. You can only have one stance going at a time and each stance lasts a minute before ending. You can only use each stance once every long rest.
Stance of Fire. When you take the stance of fire your body explodes in flame. You become resistant to fire damage and your attacks deal extra fire damage equal to your wisdom modifier. Additionally any creature that hits you with a melee attack takes fire damage equal to a roll of your martial arts die.
Stance of Air. You become like air fluid in your motions and swift in your speed. Your movement doesn't provoke opportunity attacks. Additionally once on your turn, you can replace one of your attacks with a blast air from your fists in a 20 foot cone. Any creature in the cone must make a strength save vs your monk save dc or be knocked back 10 feet and take damage as if you had punched them. On a success they take half damage and aren't knocked back.
Stance of Earth. When you take this stance roll your martial arts die. You gain a number of temporary hit points equal to the number you rolled. Additionally if you don't move at all during your turn you may add your proficiency bonus to your ac for the round.
Stance of Water. When you take this stance you gain a special attack. Once on your turn, you can replace one of your attacks with a water whip. The whip has a range of 30 feet and targets one creature. That creature must make a dexterity saving throw equal to your monk save dc or be knocked prone and take damage as if you had punched it. On a success it isn't knocked prone and takes half damage.
Enhancement of the Elements.
You have mastered the finer points of the Elements and have learned to harness their destructive capabilities. At 11th level each of your stances gain a new ability.
Stance of Fire. The fire blazing from your body creates heat like a large bonfire. All creatures of their choice who start their turn within 10 feet of you take fire damage equal to your Wisdom Modifier. Additionally when hit with a melee attack the creature now takes two rolls of your martial arts die.
Stance of Air. When in the stance all attacks against you are made at disadvantage. Additionally your blast of wind attack is now a thirty foot cone.
Stance of Earth. You gain the extra temporary hit points at the start of each of your turns as long as you don't move. Additionally once per turn you can replace one of your attacks to instead cause the earth to shake in a 20 foot sphere around you. All creatures of your choice in the area must make dexterity save vs your monk dc or take two rolls of your martial arts die. On a failed save they are knocked prone. Additionally the ground is difficult terrain for those creatures. On a success they take half damage and aren't knocked prone. The area is still difficult terrain however.
Stance of Water. You gain the ability to summon many tentacled arms of water to protect you during battle. While in this stance you gain unlimited reactions to grab ranged attacks shot at you. You can throw them back if you reduce the ranged attack to 0 as per normal rules.
Unleash the Elements
You have reached the Apex of all the Elements. You combine them together for your ultimate ability. As an action you unleash the Elements. For one minute you gain the benefits of all your stances at once. Additionally as an action you can expend all of the elements to create a beam of energy that shoots out in a 10 foot wide line that is 100 foot long. All creatures in the beam must make a dex save or take 8d10 magical damage. This ends your stances early. You can use all of your stances as per normal but you cannot use Unleash the Elements again until you finish a long rest.