If your opponent is toss and likes to build photons/dragoons, just attack with zerglings and darkswarm. I cast DS right on the photons before I attack. Your zergies will be relatively untouched by the cannons. Do this a few times and i guarantee his strategy will change. Also do this verse tanks by casting it 2 lengths in front of them, this gives zergies cover to get up close. I rarely see zerg players effectively use the zerg spells when this is like the coolest spell in the game.

CreepColony's Opinion: Consume and micro and you should be fine.