Renga

is the oldest brother of Jiga and Ruiga and the leader of the Criminal Brothers.

Background
He is the mastermind of the coup d'etat in the Land of Vegetables which resulted in the death of its daimyō. After their rise to power, the three brothers betrayed their allies, which included greedy and disloyal courtiers they had recruited, and slaughtered them all. The brothers themselves were distrusting of each other, and plotted to kill off the others in order to have more wealth and power for themselves.

Abilities
Like his brothers, Renga has a very unique and special technique presumably only he can use. In a manner similar to the Yuki clan's Ice Release, Renga has the ability to create ice. By focusing his chakra to condense moisture particles in the air, he can form thin and transparent disks of ice. These disks have several uses. They can be hurled with tremendous blunt force at a target, which will be hard to dodge because of their transparency. They can also be strung together to spy on areas both far and hidden from a distance. They also have a defensive purpose of creating highly durable shields or disks to stand on to "float". By forming the ice into a large lens, he can hover in the sky to focus the rays of the sun, which can focus into a powerful beam capable of melting and exploding the pinpointed area.

Land of Vegetables Arc
Out of all the brothers, he had the most twisted worldview, and believed most strongly in using people for his own ends. Following the death of Ruiga and Jiga, Renga attacked Naruto Uzumaki and Haruna.

He wondered why Naruto would risk so much to protect Haruna, and why Haruna would stand between him and Naruto. After using his special technique so many times, Naruto managed to come up with a way to counter it and reflect it off his forehead protector, and wounded him so badly that he was unable to continue fighting. Haruna was about to kill him to avenge her father, but was unable to go through with it. What happened to Renga after that remains unknown.

Trivia

 * The "Ren" in his name could be, as a reference to his ice-based abilities.