When the first tank rolled toward George Mason Bridge, intending to bulldoze away the rioters’ barricades, it simply stopped on the entry ramp as a blanket of darkness rolled out to cover it. The spell dissipated almost immediately, but as troops confronted by unknown magics were wont to do, Black’s command took no action. When the tank became visible again, it was turned around and backing toward the barricades. Presuming the vehicle was under hostile control, Black’s other tanks opened fire and destroyed it.