Nagare

and his partner Hokushin are members of the Watari ninja under the servitude of Hōki.

Abilities
By taking on the properties of stone, he can use the Assimilated Rock Blizzard to use stones as projectiles, and the Assimilated Rock Tank to expand using stone and crush the opponent while rolling with great force. He could also control rock powder similarly to Gaara's sand, engulfing the opponent with rock powder by using Assimilated Sand Binding Coffin and crushing them with Assimilated Sand Waterfall Funeral.

Land of Birds Arc
He eventually fought against Kakashi Hatake. Kakashi, knowing Nagare's weakness, faces him. By using his Sharingan, Kakashi was able to see Nagare's chakra emanating from a rock, the location of his real body, and uses Lightning Cutter to destroy it. After a fierce battle, he is defeated, but not killed by Kakashi.