Elemental's Blade (5e Subclass)
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Fighters of this subclass use the elemental planes to empower their strikes and defenses.
When you choose this archetype at 3rd level, you learn how to manipulate the elements. You learn one of the following cantrips of your choice: Control Flames, Gust, Mold Earth or Shape Water. You can take another one of these spells when you reach 7th, 15th and 18th level in this class. In addition, you learn the Absorb Elements spell and can cast it once per short rest. Intelligence is your spellcasting ability for these spells.
Starting at 3rd level, your ties with the elemental planes allow you to harness its power. As a bonus action you gain power from one of the elemental planes, Choose from one of the following options:
Earth: Your skin becomes as hard as stone, increasing your AC by 2.
Fire: Any weapon you hold is engulfed in flames. Weapon attacks you make deal an extra 1d6 fire damage.
Water: Your body becomes adapted to moving and breathing underwater. You gain a swimming speed equal to your walking speed, and you gain the ability to breath underwater.
Air: You start to run as fast as the wind. Your movement speed increases by 15 feet.
You gain this benefit for five minutes. Once you use this feature, you must finish a short or long rest before you can use it again.
Starting at 7th level, your knowledge of elemental magic increases. You gain proficiency in the Arcana skill if you don't already have it, and you have advantage on Intelligence (Arcana) checks involving elemental creatures, planes, magic, etc.
Starting at 10th level, your connection to the elemental planes strengthen. You gain an additional effect when using the "Elemental Empowerment" feature depending the element chosen.
Earth: Your skin becomes thicker and you can dig quickly through the ground. You gain resistance to non-magical piercing and slashing damage, and a burrowing speed of 20 feet.
Fire: Your whole body is consumed by flames. You gain resistance to cold damage, and If a creature hits you with a melee attack it takes fire damage equal to half your total fighter level (rounded up).
Water: The water around you seems to aid you while fighting. Your weapon attacks do not have disadvantage while underwater, and ranged weapon attacks you make while underwater can go beyond the weapons normal range.
Air: Attacks you make against creatures are followed by a large gust of wind. The first time you hit a creature with a weapon attack on your turn it takes an extra 1d12 thunder damage and must make a Strength saving throw. On a failed save, the creature is pushed 10 feet away from you and knocked prone.
Starting at 15th level, you learn how to shrug off elemental damage. When you’re targeted or in range of a spell or effect that deals fire, cold, lighting, or thunder damage, you can use your reaction to take no damage of those damage types from the attack. Once you use this feature, you can’t use it again until you finish a long rest.
One with the Elements
Starting at 18th level, your bond with elements peaks. You can use the "Elemental Empowerment" feature three times per short or long rest. In addition, you can use your bonus action to change the element your currently focusing on.