"Bad Medicine, Part 2 of 4: Firebreak"
*Ladytron brings her own special tank to a rumble in the desert. Things get even hotter when mighty mages battle at the Earth's core. Spartan returns to the battlefield when the Wildcats need him the most, with Gaia running wild and controlled by forces beyond anyone's imagination. A Doctor must be found – and fast – if the Earth is to survive! *Source: dccomics.com
This cover is the left half of a full image that can be formed with Authority (Vol 4) #27-B.