The archetypal Arcane Knight combines the martial mastery common to all fighters with a careful study of magic. Arcane Knights use magical techniques similar to those practiced by wizards.

Arcane Eyes

3rd–level Arcane Knight feature

Your eyes allow you to see the flow of magic around you. As an action, you can cast the Detect Magic spell a number of times equal to your Proficiency bonus. When you cast the Detect Magic spell using this feature you give off no indication that you are casting a spell. Furthermore, you do not require any verbal, semantic, or material components when using this feature. You regain all uses of this feature after you complete a long rest.

In addition, you gain Proficiency in Intelligence (Arcana) skill checks.

Spellcasting

3rd–level Arcane Knight feature

You augment your martial prowess with the ability to cast spells. Intelligence is your spellcasting ability for your wizard spells, since you learn your spells through study and memorization. You use your Intelligence whenever a spell refers to your spellcasting ability. In addition, you use your Intelligence modifier when setting the saving throw DC for a wizard spell you cast and when making an attack roll with one.

Spell save DC = 8 + your Proficiency bonus + your Intelligence modifier

Spell attack modifier = your Proficiency bonus + your Intelligence modifier

Eldritch Knight Spellcasting

Fighter Level	Cantrips Known	Spells Known	— Spell Slots per Spell Level —
			1st	2nd	3rd	4th
3rd	2	3	2	—	—	—
4th	2	4	3	—	—	—
5th	2	4	3	—	—	—
6th	2	4	3	—	—	—
7th	2	5	4	2	—	—
8th	2	6	4	2	—	—
9th	2	6	4	2	—	—
10th	3	7	4	3	—	—
11th	3	8	4	3	—	—
12th	3	8	4	3	—	—
13th	3	9	4	3	2	—
14th	3	10	4	3	2	—
15th	3	10	4	3	2	—
16th	3	11	4	3	3	—
17th	3	11	4	3	3	—
18th	3	11	4	3	3	—
19th	3	12	4	3	3	1
20th	3	13	4	3	3	1

Weapon Bond

3rd–level Arcane Knight feature

You learn a ritual that creates a magical bond between yourself and one weapon. You perform the ritual over the course of one hour, which can be done during a short rest. The weapon must be within your reach throughout the ritual, at the conclusion of which you touch the weapon and forge the bond.

Once you have bonded a weapon to yourself, you cannot be disarmed of that weapon unless you are incapacitated. If it is on the same plane of existence, you can summon that weapon as a bonus action on your turn, causing it to teleport instantly to your hand. You can use the bonded weapon as a spell casting focus. The bonded weapon is considered magical for the purpose of overcoming resistance and immunity to nonmagical attacks and damage.

You can have a number of bonded weapons equal to your Proficiency bonus, but can summon only one at a time with your bonus action. If you attempt to bond with an additional weapon, you must break the bond with one of the other bonded weapons.

Spellsword

7th–level Arcane Knight feature

When you take the Attack action, you can cast one of your cantrips in place of one of your weapon attacks.

In addition, when a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature, rather than making an opportunity attack. The spell must have a casting time of one action and must target only that creature.

Eldritch Strike

10th–level Arcane Knight feature

You learn how to make your weapon strikes undercut a creature’s resistance to your spells. When you hit a creature with a weapon attack, that creature has disadvantage on the next saving throw it makes against a spell before the end of your next turn.

Magical Defense

10th–level Arcane Knight feature

You have advantage on Constitution saving throws that you make to maintain your concentration on a spell when you take damage.

Arcane Surge

15th–level Arcane Knight feature

You are able to tap into arcane power to augment your physical prowess. Whenever you use your Action Surge, you can choose one of the following options:

• Armored. You surround yourself with arcane armor. Until the end of your next turn, and you gain a bonus to your Armor Class equal to your Proficiency bonus.
• Charge. You gain the ability to teleport up to (Proficiency bonus x 10) feet to an unoccupied space you can see. You can teleport before or after the additional action.
• Empowered. Your bonded weapons pulse with arcane energy. Until the end of your next turn, all of your bonded weapons deal an extra 2d6 force damage. At 18th–level the damage dice become 2d8.
• Eruption. You unleash an explosion of magical force in a 20–foot–radius sphere centered on you. All creatures within the area (except you) must succeed on a Dexterity saving throw, DC equals 8 + your Proficiency bonus + your Intelligence modifier. On a failed save a creature takes (Proficiency bonus d6) force damage. On a successful save, a creature takes half damage. You can unleash this explosion before or after the additional action.

Spellsword Mastery

18th–level Arcane Knight feature

When you use your Spellsword feature, you can cast a spell of 3rd–level or lower, instead of just a cantrip.