Piranha

Ruiga traps an enemy in an floating orb of water, then he summons a school of piranhas which attack the trapped target, slowly and painfully. Ruiga uses this technique on the Flower ninja genius Kikusuke and Naruto. While Naruto manages to escape death by the piranhas thanks to his comrades, Kikusuke, having not been able to use any jutsu to protect himself and having no immediate help, died.