Fish-Man Nitoryu is a swordsmanship style that combines the use of swordsmanship with a fish-man's ability to manipulate water. There are many different techniques for this sword style such as high speed attacks, direct hit attacks, and compressed air projectile attacks.

As the name suggests, this style is a variation of Nitoryu and much like Fish-Man Karate, the secret of Fish-Man Nitoryu is a fish-man's ability to manipulate the water in the 's direct vicinity; using it's power to greatly increase the swordsmanship technqiues as well as send powerful waves impacting the water within the opponent's body.

Despite being an underwater-based fighting style, Fish-Man Nitoryu is very effective on land due to being able to utilize the water in the atmosphere and make use of it to attack. The can also manipulate the water around them as if it were a tangible material, making it much easier to use in conjunction with a sword.

Techniques:

Shark Cutter: The generates water by manipulating it from the atmosphere and coating it around his both of his swords. He then jumps and swings his blades forward while spinning vertically while releasing a flowing attack in a circular motion, creating a large wheel of water that cuts through an opponents defense.

Water Tempest: The generates water from the atmosphere and coats it around both of his swords, he then slashes in a spinning formation around himself, releasing a cyclone of water and air slashes.

Hell's Waterfall: The generates water from the atmosphere before slashing downward at an opponents head, creating five large streams of pressurized water that crush the opponent.

Riptide slash: The swings and bends their blade in a winding motion along with their body and dances in a flowing pattern, slicing everything in its path.

Droplet Dash: The makes multiple consecutive slashes while twisting their body and sword in a flowing fashion to deliver multiple blows simultaneously.

Whirlpool: The fiercely twists their upper and lower body, creating a whirlpool of air that cuts anything caught in it. Its effect and efficiently is enhanced underwater, where the can draw water around their weapon to enhance their slashes.

Calm Sea: The ceases all body movements and enters a state of complete tranquility, deflecting, blocking and cutting any incoming attacks with imperceptible speed with their blade. However, its effectiveness is limited as fast and numerous attacks can break through.

Dragon Tempest: The generates a large amount of water from the atmosphere while simultaneously rotating his swords rapidly while running towards his opponent to create momentum; and slashes at them, causing the water to take the form of a large dragon that attacks the opponent.

Tide Breaker - This form requires the to run very quickly towards the opponent and jump into the air, bringing their sword down as they descend. This move is basically a defense breaker kind of deal, using the force from the descent to deal more damage.

Curling Wave - This form is a defensive one, and it requires the to rapidly spin their blade in a circle, blocking all attacks in the direction the blade is spinning.

Raging River - This form is another offensive one, requiring the to dash extremely fast at the target, in a zigzagging motion, like the flow of a river, delivering multiple strikes afterward.

Flooding Ocean - This form requires the to run at the target, and cut several places on the target's body. The will then continue to slice, until said target is cut into pieces.

Sea Storm - The runs at the target with slightly increased speed, and jumps to the side of the target, and continues to jump around them, delivering slashes all over.

River Dragon - This form requires the to utilize high spaces, and jump across them at a high speed. The then jumps down when directly above the target, and when a few inches away from them, switches the direction the blade is moving to cut the head off.

Glistening Surface - This form is another confusion tactic. The concentrates their breathing into their running, letting them go faster as they run around their opponent, becoming so fast that it looks like there are multiple copies of them, and then delivering slashes from all around them.

High Tide - This form requires the to gain the high ground again, and jumps down 6 feet in front of the target, and do a flip to gain the momentum.

Pouring Rain - This form requires the to make an accurate cut, meaning that it's meant as a finishing move, or can be used on weaker opponents to dispose of them quickly. To perform this, the 's blade will have to be lined up with the opponents neck, hence the accurate cut part. Then, the points the tip of the blade at said neck, and launching themselves at the opponent, changing the grip back to the original one, and delivering the strike.

Suijin's Power - This form is more of a strength based one. This form requires the to run directly at the target, then (If available), jump off a surface, and use the momentum from it to bring his blade down on his opponent, while spinning in mid-air.

Cascade Rush - This form is a high speed offensive move, allowing the to move faster than sight. When using this form, the concentrates all of their breathing into speed, allowing them to become this fast. Then when directly in front of the target, the unleashes a very quick barrage of slashes.

Harbinger - Through the use of special breathing techniques, the is able to forcefully pump their heart at a faster rate to increase the flow of oxygen and inflate their lungs to increase oxygen intake. The enters a state that pushes the 's body to the utmost limit and beyond its full capabilities. In this state, physical capabilities are immensely increased thereby granting the superhuman strength, and speed. Their perceptive abilities are so greatly enhanced that they perceive the world in slow motion. This technique takes a huge toll on the 's body. After it wears off the is unable to move for a period of time. The longer the spends time in this state the greater the drawbacks become. Overuse of this technique can lead to the 's death.