Sorry, that was a mix of sleep deprevation, and a sleeping pill.
No, oxygen isn't flammable itself, but when mixed with other things, it makes something burn faster and hotter, if the HBHW had more oxygen than what the Yeerks designed the dracons to be shot in, then mixed with whatever chemical agent the dracons use, could cause a flashback. (Sorry if that's not so legible, I'm still a bit loopey.
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