Start a new game then go to "Help". You can see all the animals and items.
Beat the Pacific Ocean level on Gold difficulty. This also unlocks the Gold difficulty for the Gulf of Mexico level.
Finish the pacific ocean stage.
Use the classic difficulty setting and finish the pacific ocean level.
Successfully complete the Pacific Ocean level under the platinum difficulty setting.
Successfully complete the Pacific Ocean level on the classic difficulty setting to unlock the gold difficulty setting and the Gulf Of Mexico bonus level.
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