A technique that creates a wall of water around the user to defend against attacks. This can either be done by expelling water from one's mouth and onto the ground, causing the water to rise up with tremendous might, or from using a pre-existing source. While used as a defensive tactic, it can be used in an offensive manner by directly aiming below the opponent to have the water rise up and strike them.
In the manga, the hand seal sequence for this technique ends in the same seal that activates the Byakugan, though Tobirama needs only one to use this technique. Furthermore, the anime creates a completely original and far more elaborate set of hand seals when Tobirama uses it in the form of having the right hand cupping the left hand with a thumbs-up.
In certain games, when this technique is used, it creates tidal waves that travel across the field.