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In Kingdom Hearts III, Atomic Deluge is the max-level Shotlock of the Hero's Origin Keyblade. When activated, Sora Formchanges the Keyblade into Counter Shield and thrusts it into a lightning orb, spinning to send lightning all around him. Visually, when using Atomic Deluge, Sora's clothes transform into Guardian Form.
Learning Atomic Deluge
Kingdom Hearts III