Purchase a skill.
Use the blowers to destroy all 20 Bird-bots on the Crusher level on difficulty Normal
Use the blowers to destroy all 20 Bird-bots on the Crusher level on difficulty Insane
Use the blowers to destroy all 20 Bird-bots on the Crusher level on difficulty Hard
Use the blowers to destroy all 20 Bird-bots on the Crusher level on difficulty Easy
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7501
9792
1515
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