There's a little blood throughout the series not a ton thoough.
Moderate Animated pretty Strong Violence.
It about martial art and ninja main theme. Fights are frequent but mostly bloodless -- at most, viewers see puddles of blood on the ground or light bleeding at injury site. Potentially scary monsters include zombies , a three-headed snake, swarming beetles and spiders, a broken doll marionette, a giant slug and giant larvae, a two-headed wolf, a shark, and a flesh-eating haunted castle.
A lot of non-graphic violence but this show is tamest than "Naruto Shippuden" where they have much very intense violence.
Male characters get nosebleeds sometimes.
A man is killed during an assassination attack, the body is silhouetted but very startling and intense. We later discover it was only a shadow clone of the actual man.
Naruto is poisoned in one scene and has to stab his hand to get the poison out, blood seeps out as he does it. (In Cartoon Network version, the scene is removed if Naruto using stab himself in his hand, the only showing kunai red screen, and Naruto's blood screen was digitally removed).
The battle between the Third Hokage and Orochimaru is very intense.
During the Chunnin Exams the ninjas need to battle with people that they know. In these battles a few people die but the deaths are very stylized and intense.
The battle between Team 7 and Zabuza is very graphic and intense, especially towards the end as many thugs are killed by Zabuza's rampage.
Cartoon Network & YTV: Most of the blood in the fights is either censored by shadows, camera cuts or angles, or removed all together. Some fights are shortened and a few are even removed if they are too bloody to be shown on children's television.
UNCUT:
Blood spurts from throats, runs down legs and arms, covers faces, stains the environment and weapons, and we hear the crunching sounds of bones being broken.