Kessui

The Kessui is Hannyabal's signature weapon. It is a naginata, a Japanese spear, with an extra-long spear-blade attached to each end. Each blade is an actual katana, complete with the hilt and guard, effectively making this two katanas linked together into a spear. With two blades and a long reach, the Kessui can be a powerful weapon.

Abilities
Hannyabal has show to be very skilled wielding the Kessui. He could spin it rapidly to create flames from friction to deter his opponents.
 * Hannya Carnival: Shōnetsu Jigoku Guruma (ハンニャカーニバル 焦熱地獄車): Along with fanfare being played by guards alongside him, Hannyabal twirls the sword in such a way that it creates two flaming wheels at his sides. In the Viz Manga, this is called Hannya Carnival!! Inferno Hell Wheel.