Quick recap
Filler arc. The crew wakes up with amnesia, not knowing who they are or where they came from, after a boy plays a seahorse-shaped instrument. Only Robin is spared, and she tries to figure out what happened. The real culprit is the seahorse itself, which hypnotizes people and eats their memories to become a millennial dragon. In the final fight, it shows each of them their friends and enemies to weaken them. Luffy, still remembering nothing, uses his powers by accident and takes the creature down. The memories return, but the village gets it all wrong and the crew runs back to the ship.
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