Disclaimer: I haven't finished the game yet, but,
I always set up a Reactor first, then 4 Double Blasters, and then just keep building Interceptors. Seems to work for me so far. In Flank (my first) it took alot longer because of the enemy's defenses, but once they can't even touch you because of the Interceptor spam, you'll be able to build something to take care of those. (Or your Interceptors would have done it for you)
Its so hilarious when I cast Comet Shoot on the enemy team's hero a bit after the game begins, and he rushes out to meet my minions who utterly destroy him and leave the enemy team waiting for a cooldown that does not even complete its cycle before the battle ends.
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