That really would be amazing to set tar clouds on fire with flares and flamers. It'd make even more sense for the squid to have a flamer/flare rear gun in that case - which I'm guessing is what inspired the idea originally.
Maybe tar could stay the way it is and Muse could add a new flammable gas cloud instead with this ability? Call it Fuel Dump or Diesel Cloud, but make it ineffective until actually ignited by fire.