Oath of the Coven

Source: Hexbound

Nobody is more aware of the incredible power of witchcraft than witches themselves. Witches form covens comprised of powerful spellcasters and formidable warriors, covenants that grant them tremendous power, and bonds that share their power between one another. It is no wonder that with magical groups wielding such might, someone is needed to keep the peace.
Paladins who swear to follow the Oath of the Coven are there to protect witches—most of the time, to protect them from other witches. Despite the wide diversity of covens’ values and teachings, nearly all of them include at least one Oath of the Coven Paladin. They are there to keep the peace and to protect other witches from outside threats, but also to ensure that their own companions do not go mad with power. Many are sent after witch- es who have broken the law, killed their masters, or otherwise endangered the well-being of other witches. Once an Oath of the Coven Paladin is on the hunt, very little can stop them.
These paladin witches use their witchcraft to stop spellcasters in their tracks. They are uniquely suited to counter and take down those who use magic to harm or manipulate others, and their abilities center around interrupting or resisting spells. Many witches are thankful for their presence, while many others resent them and see them as an unnecessary precaution stifling their pursuits in spellcasting, but witches have learned that a steady hand holding an unwavering sword can be the only thing stopping a coven from crumbling under its own weight.

Witchmark:

Witchmarks for Oath of the Coven paladins tend to take the form of family crests, since many of these paladins come from ancestral family lines. Other paladins have witchmarks in the shape of scars caused by damage-dealing spells, while others have the text of their own oaths as witchmarks snaking around their arms.

Aura of Antimagic

Beginning at 7th level, your very presence disrupts the flow of magic in your vicinity. Hostile creatures within 10 feet of you have disadvantage on their concentration saving throws, and you and friendly creatures within 10 feet of you have advantage on Charisma saving throws.
At 18th level, the range of this aura increases to 30 feet.