mythical item- after the beatimg tundra shogun he has a 1% chance to drop the ZeRo katana (note: the ZeRo katana has the ability of -subzero- meaning it freezes the target
Katana - Arma Blade
Top 10 Mythical Swords | Futurism
Facts and Myths About Japanese Swords - GaijinPot InJapan