The Black Ninjas were a Japanese ninja cult based in Tokyo during the 1960s. A secretive society, it was speculated that they emerged as dissenters from the White Ninjas, as the White Ninjas knew them as "apostates"; they rejected the White Ninjas' worship of the Furon god Arkvoodle and instead became bandits on the Gouka Road. They attacked civilians on the roads, and they also fought against the JSDF soldiers and local police. The Black Ninjas were initially based at Castle Kuro, which was destroyed by an alleged UFO flying saucer in 1969, upon which they made an island to the north of Tokyo their new base.