Vassal Staff

The Vassal Staff or Seven Star Staff, also known as the Staff Spirit of the Vassal Weapon. The spirit is from another world prior to being summoned to another world, the Vassal Staff is one of the eight Vassal Weapons present in the world which Naofumi currently resides in. The candidates of the weapon have been given the title of Staff Hero, whom they are generally addressed as so by the locals. The current candidate of the Vassal Staff is Aultcray Melromarc XXXII (Trash). Should Aultcray die, the next likely candidate for the Staff is Mirellia Q Melromarc.

Overview
The Vassal Staff originates from the Spear World and is vassal to the Legendary Spear along with the Vassal Projectile. The specific role of the Vassal Staff in this trio has not been stated. During the ancient past (during Mamoru's time), when the Sword/Spear World was fusing with the Bow/Shield World, the Vassal Staff was wielded by a skillful female magician.

In the modern era, the Vassal Staff was first seen in the possession of Aultcray Melromarc XXXII. He had been the Vassal Staff Hero for at least 25 years before the summoning of the Holy Heroes and has used it to great effect during the war against Siltvelt. However, Aultcray's state of mind slowly declined until he was no longer considered worthy by the Vassal Staff to be its wielder. It wasn't until his wife's death and provocation by Naofumi that regained his bearing and once again became the Vassal Staff Hero. During the fight against Takt, the Vassal Staff temporarily lent itself to Naofumi since he had his Legendary Shield stolen. The Vassal Staff was briefly stolen by Takt but it was quickly liberated, along with the other stolen Vassal Weapons. The Vassal Staff was then returned to King Aultcray.

The special ability of the Vassal Staff is that it allows for accelerated magic casting.

Power-up Method
The power-up method for the Vassal Staff is "Magic Power-up Points." This power-up method provides points to heroes as they level-up to enhance their magic spells. This heroes can redistribute these points at will. Sharing this power-up method is only effective if the heroes work together.

Trivia

 * In the Web Novel, Naofumi temporarily wielded the Vassal Staff.