Chapter 25: Methanosians
They clearly use methane, from their rotting bodies, as fuel for their fireballs. They secrete some kind of super growth serum for plants, which also contains chemicals that communicate with the plant, telling them to seize someone. The spray also contains chemicals, possibly the ones previously mentioned, that can put humans to sleep. As for his origins, I would have to guess bacteria living in a compost heap, and that his body is actually made of several very different, but still symbiotic and with the same DNA, cells. It is possible that his compost body is partially food for some of his cells. He's odd, being alive and functional while being rotting compost.
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