The theme for this one is a pony in a competition. In which Lamp explains what's up with with the harpies. In case it's not terribly clear, the thunderbird was the first one, the gust of wind that took Summer away was the second one (she landed when the sisters were busy being reunited) and the two of them have a contest going at who can swoop up more ponies. Right now neither one is doing very well. And Lamp is there to get them to cut it out.