After she has an adverse reaction to the revelation of Diana'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.
Skitter was teleported into a building, was shot and then looked in a burning building. This pissed Skitter off.
Echidna is loosed on the recovering Brockton Bay