"As some of you might know," Ms. Amelia began, her voice a soothing yet fluent tone, honed from years of captivating students. "Wyndham Leavenworth proposed the theory of mana. Imagine mana like a lifeblood, coursing through our very being, just as water flows through rivers and streams. The mana pool, then, acts as the vessel for this vital essence. Each of us possesses a pool of a certain size, ranging from a mere trickle held within a clay cup to a vast reservoir contained within a colossal iron tank."