Momochi Zabuza:
Momochi Zabuza was born in Kirigakure and was known from a young age as the "Demon of the Hidden Mist". This title is a result of his singlehanded slaying of all the graduating Academy students in the village one year, bringing an end to Kirigakure's custom of pitting students against their classmates in battles to the death. Zabuza would go on to become one of the Seven Shinobi Swordsmen of the Mist where he acquired his zanbatō, which he enjoyed sharpening in his spare time. Zabuza also became a member of Kirigakure's ANBU division, honing his stealth skills to a great degree.
At some point in time, Zabuza found a young boy named Haku wandering the countryside, and offered to take Haku in as his tool. Haku accepted and became loyal to Zabuza, learning from Zabuza and protecting him whenever necessary. Zabuza eventually attempted a coup d'état on the Land of Water by trying to assassinate the Mizukage. The coup failed, forcing Zabuza and his subordinates to leave the country. In retaliation, Kirigakure sent out ANBU personnel to kill Zabuza, who managed to evade them at every turn. In the hopes of gaining funds for a second coup, Zabuza became a hired assassin, killing anyone if the price was right.
Being from Kirigakure, Zabuza excelled in water-oriented jutsu, which he often used to make his assassinations easier. By using the Hiding Mist Technique, Zabuza could blind his target and use his ANBU training to find them in the thick mist based only on the sounds they would make. Once found, Zabuza would use Silent Homicide Technique to silently kill the opponent without their noticing his presence. This talent with assassinations appears to be well-known, as even the ninja of Konohagakure were familiar with Zabuza's history.
The Great Spirit of Water (Mizu for short):
The great spirit that controls all of Water
