Under Ninja manga volume 3 features story and art by Kengo Hanazawa.

After what seemed to be a moment of quiet among ninjas, now the Tokyo suburbs appear to be the center of violent ninja activity. Moreover, ground zero might be a rundown apartment building as a multi-factioned ninja war takes place in broad daylight! Ninja wannabees versus rogue ninja versus career ninja! And what of the casual ninja in the shopping arcade?! Make sure your head's on a shivel or you might get a shuriken to the face!