At the risk of being a complete killjoy here...

Unless you and/or your friend are actually trained in pyrotechnics, preferably with a state certification (and you might very well be, in which case, ignore everything I'm about to say) I would refuse to get involved with this. At all.

Especially the whole "while standing in the middle, he's going to light it" thing. That sounds like a really great way to light yourself on fire, especially if he's going to be in full costume at the time. Nitrocellulose isn't a joke or a fun party trick. It's legitimately dangerous and should be treated with respect.

-Merc
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