To get the Millan's Treasure Hunt option in the options menu you must get all 6 gold medals (including the one on Gossick). When you get all 6 gold medals you will get this option in the option menu. Good Luck in finding all 24 treasures.

To get this option you must have at least 3 gold medals on any world. Once you get at least 3 you will see this option in the options menu. In this mini game you will race one of the snowman. You get the slider. Good Luck on beating him.

To get the Gold Bomber option you must get 5 gold medals. When you get 5 gold medals you will see the Gold Bomber in the option menu. This is a set of 3 more levels. You start in the sea. You will be totally gold. Good Luck on beating these 3 levels

To get to Gossick (a hidden planet) you must get the special bombs in every level. It is very simple to get the special bombs. But it is impossible to get a gold medal on every level. To get a gold medal place all your clear points on 5. Gossick will then be avalible.