Demon Imperial Sword Zanvat Sword

The Demon Imperial Sword Zanvat Sword (魔皇剣ザンバットソード) was a sword of great power crafted and used by the previous King until he tossed the weapon into Castle Doran's wall. By 2008, after sensing the power of Wataru as he evokes Kiva's Flight Style, the sword forced itself out of Castle Doran's walls.

The Zanvat Sword is soon after modified with a living hilt named Zanvat-bat (ザンバットバット, Zanbattobatto), called "Zanvat" for short, who was created from the Life Energies of the Arms Monsters to control the unstable powers of the blade from evoking Wataru's Fangire blood. Though Wataru is accepted as an ideal user, he has yet to fully master the Zanvat Sword's true power.

When used by Kiva in Emperor form, its finishing attack is the Final Zanvat Slash (ファイナルザンバット斬, Fainaru Zanbatto Zan) where Kiva's power is focused into the Imperial Blade (インペリアルブレード, Inperiaru Burēdo). The attack is powerful enough to destroy giant monsters such as Sabbats and even a Mother Sagarc. It is shown in OOO, Den-O, All Riders: Let's Go Kamen Rider that Kiva can use the Zanvat Sword without transforming into Emperor form, but cannot use the Wake Up finisher.