# Mage Slayer *Source: Player's Handbook (2024) p. 205* **Prerequisite**: 4th You gain the following benefits. **Ability Score Increase.** Increase your Strength or Dexterity by 1, to a maximum of 20. **Concentration Breaker.** When you damage a creature that is [Concentrating](Mechanics/CLI/rules/conditions.md#Concentration), it has Disadvantage on the saving throw it makes to maintain [Concentration](Mechanics/CLI/rules/conditions.md#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.