Mages have often boasted of being undefeatable thanks to their magic and other supernatural abilities. A Cursebreaker is a fighter who easily challenges that notion.

Level 3: Know Your Enemy

At 3rd level, you gain the ability to see through your enemy's magical enhancements. As a bonus action, you make an Intelligence (Arcana) check against a creature you can see, contested by the target's spellcasting DC. If you succeed, you learn about any spells or magical effects affecting it.

You gain advantage on this check if you have successfully hit the target with a weapon attack before using this ability.

Level 3: Close Distance

Starting at 3rd level, when a creature that you can see within 30 feet of you casts a spell, you can use your reaction to move up to your speed towards the creature and then make one weapon attack if within 5 feet of it.

You can use this feature a number of times equal to your proficiency bonus and regain all expended uses when you finish a long rest.

Level 7: Magic Resistance

Starting at 7th level, you being to learn how to better defend yourself from spellcasters and their spells.

Whenever you finish a short or long rest, you gain resistance to one damage type of your choice: acid, cold, fire, lightning, necrotic, poison, psychic, radiant, or thunder. This resistance lasts until you use this feature again.

Level 10: Break Focus

Starting at 10th level, when you damage a creature that is concentrating on a spell, that creature automatically fails its saving throw to maintain concentration.

Level 15: Improved Magic Resistance

Starting at 15th level, your experience taught you how to fight against mages even better. You gain advantage on saving throws against spells.

Level 18: Cursebreaker

Starting at 18th level, your blade can slice through magic. Once per turn, when you hit an object or a creature with a weapon attack, you can end one spell or magical effect affecting it.