Gilda, a cow on Mean Street, will ask you to retrieve an axe from the Slopes area of Mickeyjunk Mountain. Obtain the axe and go to Oswald's lair. Thin Oswald's huge face in the floor to find a hidden room. At the end of the secret passage you'll encounter unthinnable bars. DO NOT use the axe to explore the area, but instead go back to Gilda. You'll be able to come back to Mickeyjunk Mt. later in the game and pry open the bars anyway -- even without the axe.This quest earns you both Hero and Scrapper credit.