Senju Tobirama is the Second Hokage, younger brother of Hashirama Senju. He has white hair, a severe expression, black robes, and blue armor. He is cautious and suspicious, wielding a Water Needle finger technique. He monitors Kozō constantly, testing his loyalty by leaving Hashirama cells as bait. He kills Uchiha Izuna in the past using the Flying Thunder God technique. He authorizes the formation of the Anbu, led by Shimura Danzō. He permits Kozō to take Hashirama cells but keeps his brother's body guarded. He is perceptive, able to sense Kozō's intentions and motives. He questions Kozō about Katō Dan and the Spiritualization Technique, suspecting his knowledge of the future. He continues to watch over Konoha after Hashirama's death.
