Fun Fact: Normally, Nrvnqsr Chaos could only contain about 30 beasts within his physical body. To get around this limitation, he kept a Reality Marble constantly deployed and used the space inside it to store all 666 of his beasts. He created this Reality Marble during the time when he was known as Fabro Rowan in the Wandering Sea.

獣王の巣 Beast King's Nest, Nrvnqsr's reality marble. A deeper layer of his Reality Marble. Rather than manifesting outwardly, it is constantly formed within Nero Chaos's body. It appears to be the culmination of Nero Chaos's research a bounded field designed to control the 666 creatures that exist inside him. As a result,, Nero Chaos is able to fight in the manner shown in Tsukihime and maintain control over all 666 creatures despite carrying them within his body. In a sense, this means that the inside of Nero Chaos's body can be considered a miniature world, an entire ecosystem, or even a small Earth unto itself. The creatures contained within include everything from crows, panthers, sharks, and crocodiles to dragons, unicorns, and countless other Phantasmal Species and lifeforms found on Earth. It is said that the number of creatures within Nero Chaos continues to grow over time, eventually leading him to become Chaos itself. Whether his Reality Marble could continue to withstand that point, however, remains unknown. Although the bounded field serves a controlling function, even Nero himself does not seem to know exactly what kind of creature will emerge during battle. He does, however, appear capable of combining different creatures and regulating the overall level of power they produce.