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You can reach the Ice world by going through the cave under the underground passage to Purapril. Do some shopping in Childam and meet the fortune teller, she will entrust Shabo to you. This little fellow helps Shion defeating enemies.

Inside the Ice Palace hit the dog statues and pull the ropes. You have to find 2 gems in this palace, they are quite easy to find. After you've got the gems and the pygmy boots jump on the platforms in the middle to get up. Now install both gems in the statues by pressing up. Defeat the Ice bomber and go back to Begonia.