Like most Keyblades in the series, the Rainfell is a Keyblade of the Realm of Light. Rainfell's blade is thin and predominantly a dull, metallic blue color. There is a teardrop-shaped gap in the base and near the tip of the blade's shaft. The head of the Keyblade is roughly diamond-shaped, though the left corner of the diamond is absent and there is another, small, white diamond on the inner edge of the right corner. The teeth are formed by four blue spikes lining the outer edge of the Keyblade's head. The handle is smooth and black. The guard is angular, predominantly white, and does not fully connect to the Keyblade. The Keychain links and its token are all made up of water droplets.
"Rainfell" is a corruption of the Keyblade's Japanese name, Rainfall. Both names, as well as the overall design of the Keyblade, refer to Aqua's own name, which means "water" in Latin. [Source: hkwiki]
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