Sorcerer/6th

Metamagic

At 6th level, you learn to more flexibly cast spells. You gain the Metamage feat, even if you don't met its prerequisite. If you already have this feat, you can instead gain any other feat for which you qualify.

Antimagic

You can overpower and break the magic of others while making it look easy. At 6th level, you learn the spells counterspell and dispel magic and they don't count against your spells known. If you already know either spell, you can instead learn another sorcerer spell with the same points (or the same level).

Whenever you cast counterspell or dispel magic, you always have advantage on any ability check called on by either spell.