Arcane Knowledge: 

At 3rd level, you gain proficiency in the Arcana skill, if you already have proficiency in Arcana, you instead gain a proficiency in a skill of your choice. 

You also can cast Detect Magic at will.

Arcane Drain:

Starting at 3rd level, you have honed your combat skills to include a unique ability to absorb and harness the magical properties of items you come across. By spending time and effort attuning to these items, you can channel their essence to empower yourself in battle. Whenever you find a magic item, you can spend a short rest absorbing its magical energies. Once you have absorbed a magic item, you gain access to its unique abilities, gaining buffs based on the rarity of the absorbed item.

Common: When you absorb a common magic item, you gain temporary HP equal to your Fighter Class level.

Uncommon: Absorbing an uncommon magic item infuses your strikes with elemental energy. Choose a damage type (fire, cold, lightning, acid, or thunder). Your attacks now deal an additional 1d4 damage of the chosen type for the next hour. If chosen twice, you must choose a different damage type for each.

Rare: Absorbing a rare magic item enhances your reflexes and agility. You gain advantage on Dexterity saving throws for the next hour, allowing you to nimbly evade spells and effects.

Very Rare: When you absorb a very rare magic item, your combat prowess reaches new heights. You gain an extra action on each of your turns that can only be used to make an Attack action. This benefit lasts for 10 minutes.

Legendary: Absorbing a legendary magic item grants you the ability to unleash a surge of incredible power. Once during the next hour, when you score a critical hit, you can activate this ability to deal maximum damage with that attack.

You can only have two magical items absorbed at a time. If you absorb a new magic item and already have the maximum number of absorbed items, you must choose which previously absorbed item to release in order to make room for the new one.

When a magic item is absorbed, the arcane energy of it is absorbed and it becomes a normal, non-magical item.

Arcane Sacrifice: 

At 7th level, when you are within 30ft of someone taking magical damage that is not bludgeoning, piercing, or slashing damage, you can, as a reaction, take half of the damage that they would take. This damage cannot be reduced in any way. You gain uses of this equal to your profiency bonus. You regain all uses of this ability after a short rest. 

Arcane Absorption:

At 10th level, as a reaction when you are hit with a spell that targets only you and deals damage, you can instead absorb the spell and take half damage, the caster takes the other half of the damage you would take.

At level 18, you instead take no damage and the caster takes full damage.

Once you use this ability, you cannot use this ability until you take a long rest.

Arcane Advantage: 

Starting at level 15, you understand how to take advantage of those who would be resistant to certain magics. When you hit someone with an attack, you gain knowledge of their resistances and can choose to get rid of a resistance they have until the end of your next turn. If they have no resistances, you choose a magical damage type for them to gain vulnerability to until the end of your next turn. 

You can only use this ability once per round and can use this ability equal to proficency bonus. You regain uses of this ability after a long rest.

Arcane Immortal:

Starting at level 18, you can choose to become one with the Arcane. As a bonus action, you can take a form for one minute:

• You gain resistance to all spell damage.
• When you action surge, you can choose any creature within 30ft and do 1d4+1 force damage to them.
• If an ally were to fail on a concentration check to keep a spell up, you can use your reaction to make it so they succeed instead.

You regain use of this form after a long rest.

Arcane Knowledge

At 3rd level, you gain proficiency in the Arcana skill, if you already have proficiency in Arcana, you instead gain a proficiency in a skill of your choice. 

You also can cast Detect Magic at will.

Arcane Drain

Starting at 3rd level, you have honed your combat skills to include a unique ability to absorb and harness the magical properties of items you come across. By spending time and effort attuning to these items, you can channel their essence to empower yourself in battle. Whenever you find a magic item, you can spend a short rest absorbing its magical energies. Once you have absorbed a magic item, you gain access to its unique abilities, gaining buffs based on the rarity of the absorbed item.

Common: When you absorb a common magic item, you gain temporary HP equal to your Fighter Class level.

Uncommon: Absorbing an uncommon magic item infuses your strikes with elemental energy. Choose a damage type (fire, cold, lightning, acid, or thunder). Your attacks now deal an additional 1d4 damage of the chosen type for the next hour. If chosen twice, you must choose a different damage type for each.

Rare: Absorbing a rare magic item enhances your reflexes and agility. You gain advantage on Dexterity saving throws for the next hour, allowing you to nimbly evade spells and effects.

Very Rare: When you absorb a very rare magic item, your combat prowess reaches new heights. You gain an extra action on each of your turns that can only be used to make an Attack action. This benefit lasts for 10 minutes.

Legendary: Absorbing a legendary magic item grants you the ability to unleash a surge of incredible power. Once during the next hour, when you score a critical hit, you can activate this ability to deal maximum damage with that attack.

You can only have two magical items absorbed at a time. If you absorb a new magic item and already have the maximum number of absorbed items, you must choose which previously absorbed item to release in order to make room for the new one.

When a magic item is absorbed, the arcane energy of it is absorbed and it becomes a normal, non-magical item.

Arcane Sacrifice

At 7th level, when you are within 30ft of someone taking magical damage that is not bludgeoning, piercing, or slashing damage, you can, as a reaction, take half of the damage that they would take. This damage cannot be reduced in any way. You gain uses of this equal to your profiency bonus. You regain all uses of this ability after a short rest. 

Arcane Absorption

At 10th level, as a reaction when you are hit with a spell that targets only you and deals damage, you can instead absorb the spell and take half damage, the caster takes the other half of the damage you would take.

At level 18, you instead take no damage and the caster takes full damage.

Once you use this ability, you cannot use this ability until you take a long rest.

Arcane Advantage

Starting at level 15, you understand how to take advantage of those who would be resistant to certain magics. When you hit someone with an attack, you gain knowledge of their resistances and can choose to get rid of a resistance they have until the end of your next turn. If they have no resistances, you choose a magical damage type for them to gain vulnerability to until the end of your next turn. 

You can only use this ability once per round and can use this ability equal to proficency bonus. You regain uses of this ability after a long rest.

Arcane Immortal

Starting at level 18, you can choose to become one with the Arcane. As a bonus action, you can take a form for one minute:

• You gain resistance to all spell damage.
• When you action surge, you can choose any creature within 30ft and do 1d4+1 force damage to them.
• If an ally were to fail on a concentration check to keep a spell up, you can use your reaction to make it so they succeed instead.

You regain use of this form after a long rest.