Tenkuuha, or Tenkūha (天空覇 Tenkūha? lit. "Aether Supremacy", "Sky Command", and similar) is the special technique and Z-Saber upgrade that Zero learns after defeating Storm Owl in Mega Man X4. This technique is based off Storm Owl's ability to absords damage from some types of energy attacks. This technique changes the color of Zero's saber to a violet color, allowing him to destroy energy projectiles with it. The Z-Saber does not become any stronger with Tenkuuha and there is no way to deactivate this feature, which is similar to the Kuuenzan's; once learned, the Z-Saber permanently becomes purple with Tenkuuha activated for the rest of the game.