Elemental Samurai

Using weapon abilities otherwise inaccessible, in addition, you will gain elemental abilities that can deal massive damage or make you near invincible. This subclass ensures that you will reign supreme!

Breath of the Elements

At 3rd level you gain the ability to magically infuse an element into your attacks. Choose a damage type: Lightning, Fire, Cold, Bludgeoning (water), Bludgeoning (stone), or Radiant. Each time you take the attack action, you can add 1d6 of the chosen damage type to your attack. If you use two-weapon fighting, only one attack will gain this benefit. The damage increases by 1d6 when you reach 5th, 10th, 15th, and 20th level.

Breath of Fire

Breath of the Elements will deal fire damage.

Breath of Ice

Breath of the Elements will deal cold damage.

Breath of Lightning

Breath of the Elements will deal lightning damage.

Breath of Stone

Breathe of the Elements will deal bludgeoning damage.

Breath of the Sun

Breath of the Elements will deal radiant damage.

Breath of Water

Breath of the Elements will deal bludgeoning damage.

2nd Form

At 7th level, you learn a 2nd technique using your Elemental breath. As an action, you can use your 2nd elemental technique, the damage for this technique equals 1d6 times your fighter level. Once you use this you cannot use it again until you finish a long rest. 

Elemental resistance.

At 10th level, you gain resistance to your chosen damage type, whether it is magical or not. At 20th level, this resistance becomes immunity.

3rd form

At 15th level, you learn a 3rd technique for your Elemental breath, depending on what damage type you chose at 3rd level.

Fire

You slash 10 times in every direction. Make a melee weapon attack against up to 10 creatures within 5 feet. Each creature is hit by a number of slashes equal to 10 divided by the number of targets, taking fire damage equal to 2d10 times the number of slashes it was hit by.

Ice

You point your sword causing a glacier to form in a 15 foot cone starting from the sword. Each creature in the area must make a dexterity saving throw taking 5d10 cold damage and 5d10 bludgeoning damage on a failed save or half as much damage on a successful one, the DC is equal to 8 + your dexterity modifier + your proficiency bonus. 

Lightning

You dash forward in a 10 ft. long, 5 ft. wide line at lightning speed. Each creature in the area must make a dexterity saving throw taking 5d10 lightning damage and 5d10 slashing damage on a failed save or half as much damage on a successful one, the DC is equal to 8 + your dexterity modifier + your proficiency bonus. 

Stone

You slam your sword into the ground shattering the ground and causing rocks to go flying. Each creature in the area must make a dexterity saving throw taking 10d10 bludgeoning damage on a failed save or half as much damage on a successful one, the DC is equal to 8 + your strength modifier + your proficiency bonus. 

Sun

You swing your sword, causing a crescent shaped slash to fly from it (this counts as a 15 ft. cone but without the height or width depending on whether you use it horizontally or vertically). Each creature in the area must make a dexterity saving throw taking 10d10 radiant damage on a failed save or half as much damage on a successful one, the DC is equal to 8 + your dexterity modifier + your proficiency bonus. 

Water

This technique imitates a calm ocean, causing all attacks to miss you. For the the next minute, all attacks miss you as well as spells below your level divided by 2, excluding 9th level spells and/or spells the DM decides are unavoidable, in which case you will take only half damage.

Elemental Critical

At 20th level your critical hit gain incredible potential. When you land a critical hit using either your Breath of the Elements or one of your forms, the target takes an additional 5d10 of your chosen damage type.