also, i'll rephrase my initial question
how many anti air units do i need per hawk?
and therefore how many anti air units do i need to take on 15/20 hawks?
4 or 5 fully upgraded wolverines can take out an entire pop-cap full of hawks. As for covenant units, I'd guess a 1 to 3 ratio for vampires to hawks should work, and if not, you can always make more.
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