Sometimes, a person if born with the gift of sorcery through an accident or the intervention of an extraplanar being, but sometimes, the gift is bred, nurtured, and selected, to create a powerful arcane spellcaster. The Arcane Knights are an order of warriors who use potent Abjuration magic to cloak themselves in powerful arcane defenses, while using Illusion to trick and beguile their foes. They breed their members from magical bloodlines, who are trained from birth to master their gifts.

The Order patrols the places where the border between the material plane is thin, fending off onslaughts from Unseelie Fey from the Feywild, undead horrors from the Shadowfell, the primordial Elementals from the various Elemental Planes, fiends from the Lower Planes, eldritch horrors that exist outside of reality, and even, on occasion, Celestials from the Upper Planes who insist on interfering beyond their mandates.

Unlike many martial orders, they do not rely upon weapons and armor in the traditional sense, instead cladding themselves in layers of arcane defenses more impenetrable than the heaviest of armors. Instead of swords, axes, and spears, the Arcane Warrior wields a Spirit Blade, a weapon that can cut the very soul of the person it targets.

Arcane Warriors live by a strict code, and are thus almost always Lawful. They believe more in results than morality, so they tend towards Neutrality. There are some on either end of the spectrum.  Sine believe protecting the innocent should override the demands of the Order; these Arcane Warriors tend to be Good. Others have seen the depredations of the Outsiders first hand, and would sacrifice thousands of it means keeping the world safe; these Arcane Warriors tend to be Evil.

Combat Magic

You learn additional spells when you reach certain levels in this class, as shown on the Combat Magic Spells table. Each of these spells counts as a sorcerer spell for you, but it doesn’t count against the number of sorcerer spells you know.

Whenever you gain a sorcerer level, you can replace one spell you gained from this feature (other than Mage Armor and Protection from Energy) with another spell of the same level. The new spell must be an abjuration or an illusion spell from the sorcerer, warlock, or wizard spell list. (Author’s note: There is currently no mechanism in the DnD Beyond Character Builder that allows the implementation of the above retraining mechanic).

Combat Magic Spells

SORCERER LEVEL	SPELLS
1st	Mage Armor, Silent Image
3rd	Blur, Misty Step
5th	Fear, Protection from Energy
7th	Fire Shield, Phantasmal Killer
9th	Creation, Planar Binding

Spirit Blade

Arcane Warriors do not stand in the back rows and provide support and magical artillery.  They wade into combat, trusting their enhanced defenses to protect them from harm, and then they cut into their foes with blades of pure magical force.  

Beginning at first level, you can, over the course of an hour (which can concur with a short or long rest), transform an Arcane Focus into a Spirit Blade. As an action, you can take the Attack action with your Spirit Blade, making a melee spell attack, dealing 1d6 + your Charisma modifier in Force damage. This damage increases as you reach certain levels in this class, dealing 1d8 at 5th level, 1d10 at 11th level, and 1d12 at 17th level. The Spirit Blade is considered a melee weapon for the purpose of spells like Booming Blade and Green-Flame Blade.

Additionally, while under the effects of the Mage Armor spell, you can use your Dexterity or Charisma modifier (whichever is higher) to determine your Armor Class.

Extra Attack

Starting at 6th level, you can attack twice, instead of once, whenever you take the Attack action on your turn.

Shimmering Shield

Arcane Warriors spend much of their time in battle in close quarters with enemies using large greatswords and clad in heavy armor.  They choose to forgo Armor themselves, instead trusting their extremely powerful Abjuration magic to protect them from harm.

Beginning at 14th level, while you are under the effects of the Mage Armor spell, you may now add both your dexterity and your charisma modifiers when determining your Armor Class, as you use both your agility to dodge attacks and the force of your will to deflect those that still find their mark.  Additionally, when you cast Protection from Energy on yourself while under the effects of Mage Armor, you can choose to reduce the duration to ten minutes.  During this time, it does not require concentration, and you can change the type of resistance you are granted as a bonus action on your turn by expending one sorcery point.

Ethereal Cloak

Extremely powerful Arcane Knights can briefly vanish from sight, flitting through the Border Ethereal to more efficiently maneuver around the battlefield.

As an action, you can enter the Ethereal Plane in a way similar to the Etherealness spell for one minute, and your speed is doubled.  If you enter the space of a creature, you can choose the end the effect early as a bonus action.  The creature must make a Constitution saving throw against your spell save DC, taking 8d10 on a failed save, and fall prone in the nearest unoccupied space.  If this damage reduced the creature to 0 hp, the creature explodes, and can only be restored to life through the use of the Wish or True Resurrection spells.  On a successful save, both you and the target take 2d10 Force damage, and you fall prone in the nearest unoccupied space.  You may enter the Ethereal Plane this way once, and regain the ability to do so upon completing a long rest.  You can also enter the Ethereal Plane again in this way by expending 6 sorcery points.