Vassal Katana

The Vassal Katana, also known as the Katana Spirit of the Vassal Weapon. The spirit is from another world prior to being summoned to another world, the Vassal Katana is one of the eight Vassal Weapons present in Glass' World. The candidates of the weapon have been given the title of Katana Hero, whom they are generally addressed as so by the locals. The current candidate of the Vassal Katana is Raphtalia.

Overview
The Vassal Katana was first seen plunged into a boulder of the Vassal Katana Country. As Trash II was about to try to remove it, Raphtalia came nearby and the Vassal Katana flew out of the rock into her hands. As a result, Trash II and the officials of the country branded her and her group as criminals and chased after her. After reuniting with Naofumi, they were able to get away. Raphtalia kept the Vassal Katana even when returning to her world from Glass' World.

During the first confrontation with Takt, Naofumi's group was overwhelmed and Raphtalia decided to stay behind to allow their group to escape. However, the Vassal Katana transported her to Glass' World. She worked with the heroes there to confront other vanguards of the waves.

Power-up Method
The power-up method for the Vassal Katana is "refinement." This uses materials to increase the "refinement" of the weapon which will increase the power of the weapon and show a plus beside the name. This can be done multiple times but there is a chance of failure.

Trivia

 * The Vassal Katana is a symbol of national strength of the Vassal Katana Country in Glass' World.
 * In the Web Novel, Eclair Seaetto wielded the Vassal Katana.