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Excidium
P. banal
It looks like just an excuse to have a flying big daddy in the flying city.As for songbird, I have no idea, I agree that it didn't make much sense. What is he even? Did comstock and his scientists make him?
These guys:
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Also don't make any sense. In the final game there's only like two or three of them in a single stage and you have to sneak their line of sight when the whole concept was that their hearing is amplified by those huge tubes and they're actually blind.