Roronoa Zoro has used many notable weapons and swords over the course of One Piece so far and this is everything fans know ...

In total, 31 Japanese swords of various styles line an exhibition room at the museum. Some of them are as valuable as government-designated important cultural properties, officials said.

It has been said that the samurai's sword was his soul ... the katana's two different types of steel gave it optimum qualities for both, making it a highly versatile weapon in battle.