Open every chest in the game, then speak to the sleeping Katz in Katz' Village as Sheena to recieve her Treasure Hunter title.
The Katz offer a service to collect missed treasure but they are unreliable at best. Some chests are lost forever, even with their services, and they even replace one chest with another item? This guide is pretending they don't exist, but if you're desperate, they might be worth your time.
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