Skill Guardian

You have honed your proficiency with particular skills, granting you the following benefits:

• Increase one ability score of your choice by 1, to a maximum of 20.
• You gain proficiency in one skill of your choice.
• When a creature within 5 feet of you makes an attack against a target other than you (and that target doesn't have this feat), you can use your reaction to make a melee weapon attack against the attacking creature.