Mage Slayer (Dexterity)

You gain the following benefits.

Ability Score Increase. Increase your Dexterity score by 1, to a maximum of 20.

Concentration Breaker. When you damage a creature that is concentrating, it has Disadvantage on the saving throw it makes to maintain Concentration.

Guarded Mind. If you fail an Intelligence, a Wisdom, or a Charisma saving throw, you can cause yourself to succeed instead. Once you use this benefit, you can't use it again until you finish a Short or Long Rest.