After she has an adverse reaction to the revelation of Dinah's kidnapping, Coil realizes Skitter is likely to turn on him at some point.
Coil starts taking many precautions in case of betrayal and sets up to betray Skitter first. When sent to intimidate the Mayor Trickster carries recording devices for Leet to create the "famine engine", a device that mimics Skitter's power.
At the same time the undersiders, mainly Skitter and Tattletale, begin planning to defeat Coil. they do not tell the others about the plan to a full extent, insuring information hygiene.
Skitter was teleported into a building, was shot and then looked in a burning building. This pissed Skitter off.
The Undersiders subvert and absord all of Coil's wealth and connections.
Echidna is set loose on the recovering Brockton Bay.