I've seen videos of "dragon's breath", but I don't think it has the sticking power of something like napalm. I prefer flechettes. Damn shame there are no scimitar shotshells left. Those were basically a stack of razor blades inside the shot cup.
"Dragon's breath" has nothing on a little trick they invented for the 175mm gun in Vietnam. For direct fire, they didn't even use a projectile. The powder charge is five feet long, and they's soak every increment except the base in diesel fuel. The flame was 300 meters long. And except for a bit of soot, it left the bore nice and clean.
Holey moley... how about a little *fire* scarecrow? hehehe...