The archetypical antimage focuses on the development of the physical powers needed to take on magic users. They train themselves to defeat even the most potent of spellcasters, undermining their magic to protect their allies. A burning hatred for witches fuels these fighters, and their fighting style originated from a society where magic users were shunned and exiled. Compelled to fight the threat of evil mages and thwart the plans of those who misuse magic, many of these fighters leave their homes to embark on glorious adventure.

Magical Dominance

Beginning when you choose this archetype at 3rd level, you gain proficiency in the Arcana skill and you learn to forcibly revoke the power of channeled magic.

When you successfully hit a creature that is concentrating on a spell and their concentration isn't broken by your attack, you may attempt to overpower their magic. Make a contested Arcana check against the concentrating creature. If you succeed, their concentration ends immediately.

You can use this feature a number of times equal to your Proficiency Bonus, with uses resetting after a long rest.

Witch Hunter

Also at 3rd level, you can use your Bonus Action to increase your awareness of magical forces. Until the end of your next turn, you know the location of every spellcaster, active spell, and magic item within 60 feet of yourself.
The ability can penetrate most barriers, but it is blocked by 1 foot of stone, 1 inch of common metal, a thin sheet of lead, or 3 feet of wood or dirt. You can use this feature a number of times equal to your Intelligence modifier (minimum of once). When you finish a Long Rest, you regain all expended uses.

Arcane Evasion

Starting at 7th level, you gain the ability to stem the damage of magic against you. When you are subjected to a spell or magical effect that forces you to make a saving throw to take only half damage, you instead take no damage if you succeed on the saving throw, and only half damage if you fail. Additionally, you are immune to critical hits from spells.

Profane Fighting

Starting at 10th level, you have learned to not rely on magic to defeat powerful foes. All weapon attacks that you make ignore immunity and resistance to nonmagical damage. Additionally, when you take the Attack action and only attack with nonmagical weapons, you can make an additional attack as part of that action.

Improved Arcane Evasion

At 15th level, you add your Proficiency bonus to any saving throw you make against a spell or magical effect and your Arcane Evasion feature applies to all allies within 5 feet of you.

Magical Retribution

Starting at 18th level, you can punish mages that dare to attack you or you allies. When you or a friendly creature within 5 feet of you take damage from a spell or magical effect, they take only half of the triggering damage, rounded down. Additionally, If the creature that cast the spell or caused the magical effect is within 60 feet of you, you can use your reaction to make a contested Arcana check against the creature. If you succeed, the creature takes the other half of the damage.

You gain expertise with the Arcana Skill.