Is the Palace of the Dragon King a jutsu or a space dimension

king dragon jituThe Wood Dragon Jutsu is a technique that was created by the First Hokage, Hashirama Senju, that creates a giant, wooden dragon capable of overwhelming Tailed Beasts by restraining them and suppressing their chakra by absorbingLava dragons are former red dragons that have been transformed after being surrounded by lava for too long.[1] They reside in the Lava Dragon Isle in the Wilderness (between level