Shadow Shield (Japanese: ファントムガード Phantom Guard) is an Ability introduced in Generation VII. It is the signature Ability of Lunala.
Shadow Shield reduces damage taken from damage-dealing moves by half when at maximum HP. It does not reduce the amount of HP taken from moves that deal direct damage.
Unlike Multiscale, Shadow Shield is unaffected by Mold Breaker, Teravolt, and Turboblaze. In addition, Moongeist Beam and Sunsteel Strike do not ignore Shadow Shield.
Shadow Shield has no effect outside of battle.