One of the things we used to do with WD-40 was to spray a dense line of product on the ground 10 feet or so in front of us, then ignite the spray and flamethrow to the line which would ignite and create a wall of fire. I like the idea of building a wall of flame to hide/prepare behind.

A can of flammable spray material seems much less likely to be considered a contraband weapon as well. It is also something kinda everyday. The pluses just keep adding up. Some of those Wasp killer spray cans throw a spray a considerable distance. The waterbased ones won't likely work, but those more traditional petroleum mixes might burn quite nicely.

I gotta think if a dog is on fire, he is just gonna lose interest in doing anything else but get away from it, which given their level of intelligence means running to the hills.

Disclaimer: a burning dog running through the woods is probably a big forest fire hazard. If you are going to test this theory, make sure you are in a controlled environment.