It may also be based on mythical creatures such as the Qilin, who shares the Japanese-to-English translation with giraffes, further explaining its long neck; and the serpopard, a mythical animal resembling a leopard with a long, serpent-like neck. Raging Bolt may also take its inspiration from an archaic word for giraffe, camelopard, which is derived from "camel" and "leopard".
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This somewhat explains why Raging Bolt looks like a giraffe. This is because it's based on a giraffe, meaning they have to somewhat incorporate it into the design, leading to Raging Bolt looking like a giraffe, with it's long neck and stripy(?) body. Look at Girafarig. It has to look like a giraffe, but if it didn't look like a giraffe, (as it is based off of a giraffe, it has to look like one to convey the message that it is a giraffe) it might as well just be Farig.