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The ground here is all icy. You begin the stage defeating wave after wave of enemy. You'll receive a large heart from the first pipe gushing green liquid, and a Batarang from the second.

[edit] Penguin

The final showdown, Penguin has three bars of health and some tricks, but is fairly easy. When you defeat him, you'll receive 8,000 points.

Congratulations on completing the game!