Aura Knight

By harnessing and manipulating the mystical energy known by monks as ki, Aura Knights rather than enhancing their inner body, wrap this energy around their weapons and armor by projecting this aura out from themselves. This aura not only makes their attacks stronger but provides an added layer of protection to the knight making them a perfect front-line warrior. That is if their aura can withstand the hits they take, as most of their abilities rely on using it. Losing their aura makes them vulnerable making it the worst-case scenario for someone fighting toe-to-toe with some horrible monstrosity.

Aura Shell

3rd-level Aura Knight feature

Your inner aura awakens forming a thin but sturdy film-like barrier around your body protecting you from harm, invisible to most, and becomes visible whenever you are hit. As a bonus action on your turn, you can activate your aura shell which grants you a pool of hit points equal to twice your fighter level + your Intelligence modifier, separate from your normal hit points. It can absorb slashing, piercing, and bludgeoning damage, taking half of the damage dealt by attacks that hit you which deal those damage types; the rest of the damage you take normally. If the damage reduces your shell to 0 hit points, you take any remaining damage.

While your shell has at least 1 hit point, it regains 1d4 hit points at the beginning of each of your turns. You can dismiss your aura shell as a free action and can activate it again on your next turn as a bonus action, the remaining hit points remain the same and it does not regain any hit points when inactive. Your shell is not affected by any spells or effects that heal or grant additional hit points. The number of hit points your shell gets back at the beginning of your turn increases to 2d4 at 15th level.

As a bonus action, when your aura shell has 0 hit points you can reconstitute your aura; regaining half of your maximum aura shell’s hit points when you do. You can do this two times and regain all expended uses of it when you finish a long rest.

Alternate Defense

3rd-level Aura Knight feature

While your aura shell has at least 1 hit point remaining (it doesn't need to be active) and you aren’t wearing armor, your Armor Class equals 13 + your Dexterity modifier. If you are wearing armor, you can use your Alternate Defense to determine your AC if the armor you wear would leave you with a lower AC. A shield’s benefits apply as normal while you use this feature.

Aura Projection

7th-level Aura Knight feature

Your control over your aura now covers your weapons and ammunition. While your aura shell has at least 1 hit point (it doesn't need to be active), your weapon attacks become magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage. While your aura shell is active you can use a free action to make a temporary semi-transparent weapon made out of aura that only you can use. The conjured weapon deals 1d6 force damage and uses your Intelligence modifier for attack and damage rolls. Its shape and size are up to you, if it is a ranged weapon the ammunition used to make the attack disappears at the end of your turn.

The damage dice for your conjured aura weapon increases when you reach certain levels in this class, increasing to a d8 at 10th level, a d10 at 15th level, and a d12 at 18th level.

Strengthened Aura

10th-level Aura Knight feature

If your aura shell breaks due to force damage you can choose to not take any of the remaining damage and instead be pushed 5 feet away. In addition, your aura shell can now absorb all the damage dealt instead of only half, you can use this a number of times equal to your Intelligence modifier (minimum of 1). You regain all expended uses of this ability after a short or long rest.

Altered Shell

15th-level Aura Knight feature

You can manipulate aura to give you certain benefits. When you first summon or reconstitute your aura shell you can choose one of the following enhancements which remain until your aura shell breaks or is dismissed:

Elemental Aura. Your shell is resistant to fire, cold, or lightning damage; you choose the type when you gain this feature. It can now absorb that damage type. Your weapon attacks deal an extra 1d4 damage of the type you chose. You gain proficiency in Athletics and your proficiency bonus is doubled for any ability check you make that uses it.

Enhanced Reflexes. You can use a bonus action to take the Dash action and you can run along vertical surfaces while moving (if not wearing heavy armor or a shield). You reduce any falling damage you take by an amount equal to your fighter level. You gain proficiency in Acrobatics and your proficiency bonus is doubled for any ability check you make that uses it.

Linked Projection

18th-level Aura Knight feature

When your aura shell is active, as an action, you can copy the added effects of a magical weapon, such as extra damage dice or bonuses to attack, and add them to your conjured aura weapon as long as you are attuned to that item. If the magic item has a number of charges, you can use those abilities with your conjured weapon but the charges are still expended on the original magic item like normal. You lose the copied effects if your shell breaks, is dismissed, or if the magic item is destroyed.
(e.g. You can add the extra 2d6 fire damage and light source of a Shortsword FlameTongue but you can't add the 1d6 slashing damage from the Shortsword.)