The Aether Twin is a fighter who never fights alone. They are a rare breed of magic user who has given up their ability to cast spells in order to be able to summon a spectral copy of themselves so as to control the battlefield and keep their back covered at all times.

"Double the Self, double the fun." -Anonymous

Arcane Splinter

At 3rd level, when you choose this archetype, you gain the ability to summon an arcane splinter. This splinter is an ethereal copy of yourself and is easily distinguished from you if you are present.

You may spend a bonus action to summon your splinter and have it appear within 30 ft of you in an unoccupied space you can see. On your turn, if you can see your splinter, you can use your bonus action to have it move up to 25 ft and use its action. It also has its own reaction but it cannot use both its action and reaction in the same round. Actions it can use are listed below.

Your splinter cannot take damage, but it is dispelled if you are knocked unconscious, or it is targeted by a dispel magic effect. If your splinter is dispelled, you must make a DC 14 Wisdom check at the start of your turn to be able to summon it again.

• Attack. You may use your splinter's action or reaction to make a single melee attack or opportunity attack. It copies the weapon you are using and its properties but does not do the same damage. All attacks made by a splinter deal twice your Wisdom modifier in force damage. The splinter uses your attack bonus on attack rolls.
• Martyr. You may use your splinter's reaction, and reduce the damage of any attack or spell by an amount equal to 1d10 + your fighter level. If the damage reduced is less than the amount taken, the splinter remains but is moved adjacent to you. Otherwise, your splinter is dispelled.

Back to Your Back

7th-level Aether Twin feature

At 7th level, you have learned to fight alongside yourself and gain advantage on attacks made against creatures that your splinter is adjacent to. Additionally, enemies have disadvantage to attack you if your splinter is adjacent to you, as it intercepts and distracts.

Skilled Splinter

10th-level Aether Twin feature

At 10th level, your splinter has gained a greater, more stable, sentience. This allows it to act more without your guidance. Your splinter may now use both its action and reaction in a round. It also gains additional options for its reaction and its attacks deal three times your wisdom modifier in force damage

• Riposte. If a creature misses you or an ally with a melee attack and your splinter is within melee range, you may have it use its reaction to make an attack against that creature.
• Intercept. If you or an ally are the target of an attack, you can use your twin's reaction to move it up to 15 ft and give you or an ally +3 to AC

Self to Self

15th-level Aether Twin feature

At 15th level, you may spend a bonus action to switch places with one of your splinters via a quick teleportation.

Triplets

18th-level Aether Twin feature

At 18th level, your skill at using and summoning your splinter is so efficient that you now summon two splinters instead of one. When you use your bonus action to order your splinter, they may both use an action.