The hall was unusually quiet.
Even the students who normally whispered or fidgeted had gone still as the instructor turned toward the board. He didn't write immediately. He let the silence stretch, eyes sweeping across the room until he was certain he had everyone's attention.
"Today," he said calmly, "we stop pretending monsters are rare."
A few students shifted uncomfortably.
"You will hear many names for them outside these walls. Demons. Abominations. Cursed creatures."
He tapped the board once.
"We use the correct term."
He finally wrote.
Corrupted Beasts
"Monsters are not born," the teacher continued. "They are created when a mana core turns negative."
Several hands twitched, then lowered. He kept speaking.
"Every living being possesses a mana core. Humans, animals, even certain plants. The core absorbs ambient mana, refines it, and allows the body to function."
He turned back to the class.
"When that process becomes distorted—through prolonged exposure to unstable mana, violent death, extreme emotion, or consumption of other cores—the core changes."
His voice hardened.
"It becomes negative."
---
He drew a simple diagram beneath the words.
"Once corrupted, the creature enters a ranked growth cycle. Pay attention. This is not theory. This is survival."
---
Rank 1 — Corrupted Beasts
"These are the most common," he said. "Former animals."
Wolves. Boars. Birds.
"They retain only basic instincts. Hunger. Fear. Territorial behavior."
A student in the back muttered, "So they're just animals?"
The teacher's gaze snapped to him.
"No."
He let that hang.
"They instinctively seek mana-rich prey—especially humans. Not out of hatred. Out of necessity. Devouring a mana core strengthens their own."
He turned away again.
"Most of you will face Rank 1s before graduation. Many villages deal with them weekly."
---
Rank 2 — Semi-Sentient Corrupted
His tone shifted.
"Rank 2 beasts are where students start dying."
The room stiffened.
"They develop crude intelligence. They can retreat. Ambush. Target spellcasters first."
He underlined the last sentence twice.
"A single High Initiate may survive one. Victory requires coordination."
He glanced over his shoulder.
"If you underestimate them, you will not get a second lesson."
---
Rank 3 — Sentient Corrupted
He stopped speaking for a moment.
Then, quietly:
"Rank 3 beasts are rare."
He turned fully toward the class now.
"And fully sentient."
Murmurs spread before he silenced them with a raised hand.
"They can think. Plan. Remember."
Then he added, slowly, deliberately:
"They can use the abilities of the mana cores they consume."
The murmurs died.
"A Rank 3 that devours a fire mage may wield flames. One that feeds on spatial mana may tear space itself."
A student swallowed audibly.
"Some speak. Some negotiate. Some hunt for enjoyment."
He folded his arms.
"When one appears, evacuation orders are issued. Heroes are dispatched. Records are sealed."
---
Ranks 4 and Above
The teacher didn't even bother writing this time.
"Ranks four through seven and beyond are… theoretical to most of you."
His expression darkened.
"By Rank 6, reports become legends. Cities erased. Armies lost. Names that never make it into history."
He leaned forward slightly.
"If a Rank 6 appears openly, the Academy moves."
That alone told the class everything.
---
The Core Rule
"One final thing," he said, voice sharp.
"No corrupted beast can be killed unless its negative mana core is destroyed."
He tapped the diagram again.
"Destroy the body without shattering the core, and it will regenerate. Adapt. Or evolve."
His eyes scanned the room.
"This is why precision fighters are feared. Why certain affinities are… monitored."
He paused, then concluded:
"Remember this lesson. Because one day, one of you will look into the eyes of something that used to be alive."
"And you will need to know exactly where to strike."
The bell rang.
No one moved.