Nimble

Prerequisite: Dexterity 13 or higher

You have mastered the art of thinking and moving quickly. You gain the following benefits:

• As a reaction, you can impose disadvantage on an opportunity attack against you or an ally within 5 feet of you.
• When you take the Disengage action, difficult terrain doesn't cost you extra movement on that turn.
• As a reaction, when an enemy that you can see casts a spell that requires a Dexterity saving throw, you and one creature within 5 feet of you can automatically succeed on the saving throw. You then fall prone, and neither of you can use the dash action on your next turn.