by JYoder
Follow up question...
We had a situation where I had 2 of these cards stacked and I took out the 4 life villain on the Rooftops with 0 cost to my attack total. However, I then played the Storm card to move any Villain to a new city space. I moved another 4 life villain to the Rooftops.
Most hero abilities have an immediate effect, such as draw a card, etc. But Storm's Lightning Bolt implies an ongoing affect as it says, "Any Villain you fight on the Rooftops this turn gets -2 attack." So I defeated the second villain for 0 cost to my attack total too. I assumed we played it correctly, but just wanted to be sure.
Especially since the second card was "Endless Armies of Hydra" that pushed yet another villain card onto the Rooftops, which I again took out with ease.