Flaming Arrows play similarly to Falconets of most European civilizations. They are somewhat weaker than Falconets but move as quick in Limber as in Bombard mode, making them more mobile on the battlefield, but less outside of battle. They can devastate formations of enemy infantry and can sink ships as well. They are less effective against buildings but in groups can easily take them down. As with other artillery units they are weak against cavalry, which can close the distance before taking too much damage.
“The flaming arrow was exactly what its name suggests, a barbed projectile fired, in most cases, from a European cannon, as the Japanese had not developed effective artillery of their own. Each arrow was wrapped with a flammable covering and ignited. There was also a more explosive version, on which gunpowder was encased in a ball located just below the barbed tip. When fired, a flaming arrow would bury itself in the wood of a gate or wall and burn, hopefully setting the whole structure ablaze.
Japanese daimyo, Tokugawa Ieyasu, had a keen interest in building more advanced artillery for his armies. He leveraged his connections with English and Dutch traders to import a variety of European model cannons. It is believed that he utilized these weapons, as well as the flaming arrow, in sieges during the famous Sekigahara campaign of 1600 that eventually led to the establishment of the Tokugawa Shogunate.”