"Magical beast 'Umbramouse'? Grandpa Kaiya, what makes an Umbramouse special, and what is its rank among magical beasts?" Renji asked, his curiosity piqued. Kaiya Tanaka, while communicating telepathically, also answered with a smile. "The Umbramouse isn't easily categorized by rank because it represents a whole species. There are two main types of rat-like magical beasts: the Terran Rodents and the Umbramice. Both are omnivorous, consuming anything from stones and bones to meat," he explained. Renji recalled seeing the black Umbramouse nibbling on a rock earlier.
"Magical beasts are classified into nine ranks, with first rank being the weakest and the Saint-level beings being the highest," Kaiya Tanaka continued. "Among Terran Rodents, the weakest are the Grey Terran Rodents. They are grey with some variations in shading. At rank four, their fur turns silver, and at rank seven, it becomes gold. Gold Terran Rodents are at least seventh rank but can go up to eighth rank."
Kaiya Tanaka shared his concerns about Terran Rodents. "Terran Rodents are fearsome due to their large numbers and extremely sharp teeth, which are more dangerous than those of the Umbramice. An army of Terran Rodents can overwhelm even a hundred thousand soldiers. Their bodies are tough and their numbers vast, making them a terrifying force." Renji imagined a massive swarm of Terran Rodents attacking an army, feeling a shiver at the thought.
"Unlike Terran Rodents, Umbramice are known for their speed and sharp teeth. While they are also numerous, they don't match the sheer numbers of Terran Rodents," Kaiya Tanaka explained. "The weakest Umbramouse is a third-rank magical beast with black fur. As they rank up, their fur changes color: turning blue at rank five and violet at rank seven. The one we saw must be a third or fourth-rank Umbramouse."
Kaiya Tanaka noted that this particular Umbramouse was exceptional. "The speed of this infant Umbramouse is unusual for its age. If it can already move as fast as a fourth-rank adult, it might grow up to be a violet-colored Umbramouse, possibly even a seventh-rank beast. I suspect it is the offspring of a Violet Umbramouse."
Renji was intrigued. "But its fur is black. How could it be a child of a Violet Umbramouse?" Kaiya Tanaka clarified, "Violet Umbramice and Blue Umbramice are born with black fur. The color changes as they grow stronger. The fur color indicates their power."
"Given its speed, this Umbramouse is remarkable. If it's as fast as a fourth-rank Umbramouse, it's impressive compared to a sixth-rank warrior like Uncle Draven," Renji noted. Kaiya Tanaka agreed, highlighting that Umbramice are renowned for their speed.
"A Violet Umbramouse is a prized magical beast, especially in its seventh rank. Many magi desire one, but they are hard to capture and tame. An infant Violet Umbramouse is rare, and taming one is even more difficult," Kaiya Tanaka said with a smile. "A Violet Umbramouse could be a powerful companion for you. It would be like having an entire army of Umbramice."
Renji's interest was piqued. "How can I tame this Violet Umbramouse?" he asked eagerly. Kaiya Tanaka, recognizing Renji's determination, cautioned him. "You need to be calm. Even an infant Violet Umbramouse, with its speed comparable to an adult of the fourth rank, is too swift for you to subdue by force or with a soul-binding magical formation, which requires at least a seventh-rank magus."
Renji felt deflated as he realized his current limitations. "I remember now. To tame a magical beast, you either need to forcefully subdue it or use a soul-binding formation, which is beyond my capability right now." Despite his disappointment, Renji was determined to improve, recognizing the rare opportunity he had encountered.