In the northwestern area, sail to the traveling ship and climb aboard. Talk to the "Doppleganger" and he will tell you that his boat's name is "The Prince of Red Lions". Also his uniform resembles Link's but with a few tweaks. He will the take you as an apprentice and challenge you to a fight. Leave and re-enter the ship. Fight him again and make more hits than last time. Exit and re-enter again. Fight him and make as many hits as you can. Under 100 hits will earn you a spoil (for example, Pearl Necklace, Princess Crown, etc.). Get more than 100 hits and you will get a Heart Container. Aim for 150 or higher.