Nrvnqsr Chaos

One of the Dead Apostle Ancestors, who was chasing after Arcueid.
The factors of 666 beasts are swirling around within his body, though it may be easier to think of it as him being equipped with 666 familiars.
Because this is essentially like having 666 lives, properly speaking he's a monster that even a serious Arcueid wouldn't be able to kill.
Despite his huge, muscular body, he is still a scholar at heart, and becomes extremely agitated when he runs into a situation he cannot understand.
As a result, he lost his cool in his battle against Shiki and ended up recklessly charging at him. Namaste, Nrvnqsr.
Perhaps due to his abilities, he is becoming more and more apathetic and indifferent toward everything. Should he continue to live for another several hundred years, odds are he really will end up degrading into nothing more than a mass of chaos.
His role did not exist in Old Tsukihime. However, in the process of paring the length of the game down to ten days, the art director came forward with the proposal that the first half of the game should be livened up a bit.
“Eh? But I don't wanna have an enemy besides Roa!”
The scenario director threw a tantrum, but in the end he relented and pulled Nrvnqsr out of the Mushroom Warehouse.
And, presto! Suddenly the flow of the story was just how the art director wanted it.
…Clever bastard.

Tsukihime Data Collection: Tsukihime Dictionary
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Real name: Fabro Rowan. Also known as “the Chaotic Horde.” He is number 10 of the 27 Dead Apostle Ancestors. He has the constituents of 666 beasts in his body, and can use each individually to serve his will. In Tsukihime he slaughters and devours all of the hotel guests in a single evening. He had 666 lives, but was destroyed by Shiki's Mystic Eyes of Death Perception.

MB Official Strategy Guide: Melty Blood Glossary
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The vampire pursuing Arcueid. One of the 27 Dead Apostle Ancestors.
The factors of 666 beasts are swirling around within his body, though it may be easier to think of it as him being equipped with 666 familiars. Because this is essentially like having 666 lives, properly speaking even a serious Arcueid wouldn't be able to kill him. Also, as one who became a Dead Apostle through magecraft, he has absolutely no interest in territory or building a faction. The only thing he cares about is completing his thesis.
Despite his huge, muscular body, he is still a scholar at heart, and becomes extremely agitated when he runs into a situation he cannot understand. As a result, he lost his cool in his battle against Shiki and ended up recklessly charging at him. Perhaps due to his abilities, he is becoming more and more apathetic and indifferent toward everything. Should he continue to live for another several hundred years, odds are he really will end up degrading into nothing more than a mass of chaos.
When he was still a human, his name was Fabro Rowan. He was a magus hailing from the Wandering Tomb, located in the northern Sea of Estray.

Tsukihime Dokuhon Plus Period: Tsukihime Dictionary Revised
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One of the 27 Dead Apostle Ancestors. Alias, Chaos. He uses all the creatures of the earth as familiars. Because of the fact that he is preserving even extinct species, he is also sometimes called Dr. Beast.
Though he had no business in Japan, he was selected as the executor of the True Ancestor hunt proposed by the White Wing Lord, and followed Arcueid to the island nation in order to defeat her.
Dead Apostles who can measure their lives in millennia require a colossal amount of energy. This has nothing to do with their strength—it is merely the compensation required to maintain such a long-lived existence. Because he is one of these millennium-class Dead Apostles himself, Nrvnqsr's appetite is voracious. It took devouring every single person in a ten story hotel just to satisfy him.
The factors of 666 beasts are swirling around within his body, but it's probably alright just to think of it as him being equipped with 666 familiars. Because this is essentially like having 666 lives, properly speaking he's a Dead Apostle that even a serious Arcueid wouldn't be able to kill.
As one who became a Dead Apostle through magecraft, he has absolutely no interest in territory or building a faction. The only thing he cares about is completing his thesis.
When he was still a human, his name was Fabro Rowan. He was a magus hailing from the Wandering Tomb, located in the northern Sea of Estray, one of the three main branches of the Association.

MB Act Cadenza PS2 Manual: Tsukihime Dictionary