Curse Basin

This is a subclass allowing you to change up magic and resistances in real time, at the cost of your body

Mystically Adapted

At the beginning of combat, or if announced before a saving throw or roll, you can appoint a type of magic to be resistant to, giving you advantage from attacks of that type. This resistance lasts for 6 minutes, and can use this feature a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest. 

Hexic Vibe

When you gain this feature, your ability to understand a spell or curse increases dramatically, not from an understanding of origin but rather being able to identifying the makeup of the magic. You gain the ability to roll any Arcana roll or any intelligence roll that would be used to identifying magic with Charisma. 

At level 14, you gain the ability to read the intention of a curse or magic to the point of disarming or flat out dispelling magic or successful rolls.

Aeolidic Physiology

When you are hit with a magic or curse you are resistant or immune to, you have the ability to store away a small fraction of the power inside the cells of your body. You can only store one type of magic in this way, but may store it for 1 week of in game time. In combat, you use a bonus action to release the magic at a target or yourself, using up the cells storing that spell like an item or spell scroll. The spell damage modifier is half the original spell, but requires no cast time or preparation 

Child of the Curse

When preparing spells after a long rest, you can use a sorcery point to create a custom spell or curse on an object. The main components of this creation are the modifications of the spell affect, the components to use the spell, and the power of the spell. Talk with your DM to help balance these custom spells.