Start the game and proceed until reaching the level selection screen. Type go planet and begin game play. Press [F10] + [Enter] during game play to return to the level selection screen, where all levels will now be unlocked.
Note: A copy of the game Captive is required for this trick. Load Captain Planet then replace the disc with Captive at the level selection screen and press Fire. A "Disk Error" message will appear. Re-insert the Captain Planet disc and continue game play.
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