Just reading the terrain modification tread i just figured...
Gobwin Knob is built mostly on top of an Uncroaked Volcano. Now if someone -let's think Charlie- found a spell to disrupt uncroaked... then the mountain itself would turn to dust
and the city would crumble to pieces. I bet such a spell actually exists... I mean the Volcano is not a decrypted, it's just a lowsy uncroaked.
Also I wonder if Wanda can actually control it while the uncroaking lasts... I bet if she wanted it, she could make Gobwin Knob burn from the other side of the world just by mentally giving it the order to erupt again... Stanley better not ever piss her off while standing over the tomb that is Gobwin Knob