One Piece Impel Down & Marineford Episode 497 Leaving the Dadan Family for Good?! The Kids' Hideout Has Been Built! ( Air Date 2011-05-08 ) Genre Action & Adventure, Comedy, Animation category. Overview "After another beating from Garp, Luffy and his friends take to the jungle and build a pirate hideout at the top of an enormous tree. First order of business: booby trap the new place!".