The second level of the terrifying prison located in the Black Star Village, this detention place is the most fearsome of all and many people who thought of commiting crimes have been quickly brainwashed not to do so by their own mind because of the fear of the great Black Star Detention Unit.
Here prisoners are trapped unable to use chakra like the rest of the levels of the detention unit using black star metal chains enchanted with chakra-supressing seals and chakra-supressing mechanism brought from the Snow Village from the far North.
Fierce Monster Hell is the second level of the Black Star Detention Unit in which prisoners are kept. It contains various wild beasts of sorts. The beasts kept here include Puzzle Scorpions and Manticores. Puzzle Scorpions are large poisonous insects that can join together to become giant centipedes. Manticores are man-eating human faced lions that will devour everything from their prey including the bones. Their human faces allow them to speak however they can only imitate what they hear like parrots as they don't understand what they're actually speaking. The words they speak are mostly things they heard from the prisoners so some of the things that they say are completely out of place. Among these regular-sized beasts kept here are also two gigantic beasts, the Basilisk and the Sphinx.
The Basilisk is a gigantic snake born from a chicken. It is a feathered mutant that possesses both snake and chicken traits. Though formidable, the Basilisk is not the most powerful beast in the level. It is considered to be the "second-in-command".
The Sphinx is a gigantic human faced feathered lion. Significantly larger than the Basilisk and much more fearsome than the other beasts, it is considered the "boss" of the level and is charged with guarded the stairway that leads out of the level. It is so fearsome that the prisoners kept in the level, and even the other beasts hide from it. Like the Manticores, it is capable of imitated speech. It randomly says the names of types of noodles and apparently understands the concept of giving thanks before meals. It is such a strong beast that it is capable of breaking the floor beneath it if it hits it enough times.
With these various beasts, prisoners kept here are forced to be chased by them through the corridors of the level. Because of the fearsome danger, prisoners often either lose the will to go on, or refuse to escape even when their cells are unlocked
Motto: Eaten and Digested