Four Island

Once you arrive at Four Island, also known as Floe Island, Gary will first come to talk to you. First, go north a bit and break the rock. Keep going north for a Star Piece. Return to where you were and go to the house next to the PokeMart. Talk to the person inside, and he'll apply a Hall of Fame Sticker to your Trainer's Card. In the upper-right hand corner of the island is a house with a Move Tutor inside. He teaches Body Slam. Next to that house is the Day-Care Center. Leave your Pokemon here to let them breed or raise their levels. Next, you surf across the pond for a Stardust, and then surf to the other side to enter the Icefall Cave.