Sacred Arrow (セイクリッドアロー, Sacred Arrow) is Mythra's Final Smash in Super Smash Bros. Ultimate.
Mythra summons Rex, who says "Mythra, now!" and performs an underhand slash to transition into a cutscene. In the cutscene, Mythra says "Concentrate, Rex.", and she and Rex hold the Aegis Sword together and point it into the sky to summon a beam of light, shouting the move's name. Transitioning into normal gameplay, they point the Aegis Sword forward to rain smaller beams of light from the sky down onto the opponents, whilst Rex says, "And, strike!", before he fires a light beam from the sword to finish the move.