The Shichiseiken (七星剣, Literally meaning: Seven Star Sword) is a light blue broad and flat sword with a brown talisman hanging from the bottom. By saying the verbal command "curse" (呪え, noroe, English TV: curse them), it can be used to sever the word soul (言霊, kotodama, English TV: spirit word) of those struck by the Kōkinjō, allowing the soul to be sucked into the Benihisago. Completing these conditions "curses" the victim; if they utter the word they have said the most during their life, they will be sucked into and trapped within the Benihisago. Whatever this word is will be inscribed onto the Shichiseiken's blade. The wielder can fold the blade to prevent the victim from seeing what it is. If their most-used word changes at any point, the inscribed word will be updated.
The Shichiseiken is revered as one of the treasured tools of the Sage of Six Paths. All five of the tools consume enormous amounts of chakra when used, so much so that normal humans would die after using the tools for only a short period of time. When the tools later came into the possession of Kumogakure, only the Gold and Silver Brothers due to their large chakra reserves were able to wield the treasures without fatal repercussions. When not in use, Kinkaku stored the sword within himself, drawing it from his own mouth when needed.
The Shichiseiken is based on a tool from the Chinese classic "Journey to the West". In this story; there are two demon king brothers, known as the Great King Kinkaku (金角大王, Kinkaku-daiō) and the Great King Ginkaku (銀角大王, Ginkaku-daiō). The siblings possess five treasured tools, one of which is called the Seven Star Sword (七星剣, Shichiseiken).
The Shichiseiken also has connections to Taoism. Seven Stars (七星, Shichisei) is the name given to the constellation of Ursa Major in China and Japan. Swords based on Taoist thought and bearing this name are said to hold the power to crush evil and protect.
In the manga, the Shichiseiken is light blue in colour, while in the anime, it is grey.