Croc: Legend of the Gobbos/Crystal Island
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This is the fifth, and final island in the game.
Levels
5-1 And So The Adventure Returns
5-2 Diet Brrrrr
5-3 Trial on the Isle
5-4 Crox Interactive
Boss Levels
You must beat boss levels to progress to the next level.
Beating a boss level also unlocks a secret level, if you collected all the Gobbos from the levels preceding it.