Are you sitting comfortably? Then we'll begin. Course 5 is the now-traditional Ghost House. Compared to most of the other courses in the game, it's difficult to find. Go into the castle through the main door. Head through one of the wooden doors to the side of the staircase. You should be greeted by a big ghost who runs away as you approach. Follow him down the passage and through the door. You'll end up in a courtyard swarming with ghosts. When you look at them, they go transparent and reveal their "contents": some have coins inside, but a large one to the left of the pool should contain something that looks like a bird cage. Ground Pound that one and the cage will come out. Go near it and you will be sucked into Course 5!