So, I decided to try out shadow. Had a look at T1 units. I thought that maybe the Tainted Snapjaws might be nice as a sort of support unit, maybe have one of them running around with your T1 ball for the debuff. Thing is, the damage was abysmal. Far less than the 280 damage would imply.
They did 119 damage against Twilight Claws in 36 seconds, 96 against Bandit Footmen in 27 seconds (after each of those they died). Against a wall they did 160 in 20 seconds, which is at least close to the minimum damage they should do (still 4*5*20/2 should be 200).
Their nominal damage is 280; maybe