Giant butt-biting caterpillers

I was cleaning the bathroom in preparation for my friends coming over. I got on my knees to clean under the toilet and saw a mess of webs and a giant, six-inch technicolor green caterpillar. I was sure that this was the source of the bite I had on my face. I freaked out and called in Matt to take care of it. His bright idea was to repeatedly throw the creature against the wall till it died. Each hit left a bright green stain on the wall.