One of the 7 swordsmen of the Mist, Zabuza carries around an enlarged sword which is his head chopping blade. He specializes in sneak attacks and is called the silent killer. He can even track his oppoents down with no visibility and just going on smell and sound along. Back in the old days of the Ninja Academy in the Mist Village to proceed to become a shinobi you must enter a battle to the death. So 10 years ago a young Zabuza killed over 100 ninja academy students with out any hesitation and recieved the name Devil of the Mist, and even the Mist Village got the nickname Blood Village. They were forced to change this ninja test due to that incident

As Zabuza grew up he tried to perform a Coup d'etat on the Mizukage but failed and had to leave the village. He brought his apprentice along with him Haku who he found as a begger on the street and just wanted to use him as a weapon. Zabuza wanted nothing more than revenge but he had no money to fund it. So along came Gato who offered to pay him for services to kill Tazuna, a bridge maker. After several close battles with Kakashi, and Zabuza is the first person to ever see Kakashi's sharigan twice. Zabuza believes to be a shinobi you must kill someone first and have no feelings. However, just before he died he finally realized you need to feel emotions if you truely want to live