While watching Ozma's Magic Painting, Dorothy sees Ojo the Unlucky not doing well at just about anything, so she decides to go help him out. None of her Kansas remedies (four-leafed clover, salt over the shoulder, that sort of thing) works, so Ozma tells her that Ojo must drink from the Fountain of Refresh in Ev. They find the fountain, but are captured by guards before Ojo can drink and are confronted by the king of Ev—the Nome King! But Ojo's "bad" luck causes the jail door to fall on the Nome King. As they're heading back to Munchkinland, Dorothy points out to Ojo how much of his "bad" luck really worked out well in the end, and therefore whether he is lucky or unlucky is just a matter of perspective.
Another fun one, but with a nice little message at the end. We get Ojo, the Magic Carpet (albeit a much different version than the one in Ozma of Oz), a magic fountain, and Dorothy even mentions Zeke. We also get a good look at the map of Oz (spoiler: it looks a lot like this one. So lots of nice little references to both the books and The Movie.