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Spider's weapon of choice for most of the series is a handheld "bowel disruptor," which causes instant and painful loss of bowel control, with various settings that allow him to vary the level of pain and discomfort the device will inflict, ranging from simple diarrhea to complete rectal prolapse. At a much harsher level, the victim has a bowel movement so dramatic and agonizing that it induces unconsciousness. While at least three times in the series, it is revealed through dialogue that the gun can be set to 'Fatal Intestinal Maelstrom'. Spider prefers this weapon because, despite being illegal, it is (usually) non-lethal and its effects are untraceable. His assistants, Channon and Yelena, have also been armed with bowel disruptors during The Cure arc.

"The FA clan are pretty much the only authority in Whitechapel that we've been introduced to and they're obviously making it up as they go along. Part of my enjoyment for this series is watching their learning curve.
I don't think anyone has questioned Kait before this, partly expediency, partly ignorance. Now they know it's going to be interesting to see if they can let her continue on as before."