its filler arc but in a same way its part of a story would
Suigutsu pick up these weapons
Name: Lightning Fangs (らいろが, Rai Rōga)
Wielder: Raiga Kurosuki
Debut (Anime): Naruto Episode 152
The Lighning Fans are twin pike-like swords, resembling dragon fangs, that are wielded by Raiga Kurosuki. Raiga can use the swords to channel Lightning Release techniques. They can conduct natural lightning as well. These swords can also be connected at the hilts by Raiga to form a larger double-bladed sword. These blades were left behind at the bottom of a river in the Land of Rivers after Raiga's death.
Suigetsu Hōzuki has stated that he wishes to obtain all the swords of the Seven Ninja Swordsmen of the Mist. As the Lightning Fangs appear in the anime filler arc, it is unknown how Suigetsu plans to obtain these swords (if at all).