Quote Originally Posted by thorofasgard13 View Post
I doubt Zabuza used one-handed seals as that's probably just like the thing that Naruto does for his KBNJ, the rest of the seals are just not shown anymore. While not only did Haku use the one-handed seals but they were shown and explicitly stated. Hand seals are not a bloodline limit (at the most they would be a clan secret)! Like it has been said, maybe he learned a specific method of using his hand-seals, my question is then who taught him as it wasn't his parents as his mother tried to hide the ability and his parents were both dead, him being raised by Zabuza who couldn't do them(or Kakashi would have said that he could also)?
Zabuza had his other hand in the water prison jutsu. He had to have his hand in there. And his seal was explicitly shown. Thus Zabuza tought it to him logically.