Zabuza has been called the Demon of the Hidden Mist; this is because during his childhood, he killed over 100 of the ninja academy graduates attending their final exam. In the exam, each student would be pitted against the other in a battle to the death. The massacre ended this tradition immediately.
His fame grew over the years, as he became both an ANBU and a member of the Seven Ninja Swordsmen of the Mist. He eventually attempted to kill the Mizukage in a failed coup d’état, and subsequently fled. Just …

As the Zabuza’a death, things were settled to normal and Tazuna can continue to build the bridge without any fear. Everyone thought that Zabuza was dead but Kakashi thought the other way, so the taught Naruto, Sakura, and Sasuke a way to train so they could better use their chakra.

A peaceful scene of a waterside home, and inside this home we find Kakashi coming to and a woman asks how he is doing. The three Genin enter with Tazuna, happy to find Kakashi awake, they all wonder about the happenings …