Shuriken Mastery

Shuriken Mastery is a skill introduced in Fire Emblem Fates. It is the personal skill of Kagero.

Fire Emblem Fates
If Kagero is attacked by an enemy with a Shuriken equipped, she will deal back half the damage received from the attack and will give them the same stat penalties she received as a result of her attack.

Trivia
Despite not being shuriken weapons, hits from Setsuna's Yumi and Iago's Tome are able to trigger Shuriken Mastery because of their stat lowering capabilities.