“She ate your rat skeleton?” Skadi asked. It was evening now and we were having dinner. I had just told her and Helena about my day.

“That must have been funny to watch.” Helena said.

“Don’t encourage her!” I protested. “I told her to not do it again.”

“You told a cat to behave? Uh… sure. That will work. Absolutely.” Skadi said.

I looked at Nyx. She was curled up and ignoring our conversation.

“Maybe I can let her hunt something. Are there any rats inside the academy?”

“I have no idea. I never saw one.” Skadi said, shrugging.

“Rats are boring, we need to hunt something bigger! It’s such a shame that you can’t leave.” Helena sighed. “We need to become stronger to protect you.”

Becoming stronger was certainly a sentiment we shared. I did not want to be weak. One day I would be the predator and not the prey.

The next day Helena and I had another basic magic class. It was always nice to see Archibald flinch a little when our teacher arrived.

“Morning class, I see everyone is on time.” Victoria said with a smile. “Be seated. Today we will cover magic fatigue.”

That was a lesson I had been waiting for.

“First, I need to explain a few basics. You all know about your core and that it produces mana. You can imagine it as a water tap. But in order to cast a spell, you first need to draw the mana into your body, imagine it as a mug. If you wanted to drink, you would use the tap to fill the mug and then have a sip. To cast a spell you pull mana into your body, from your core, then you power the spell. All with me so far?”

Shin raised his hand.

“Shin.”

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“Why does core size matter then? Should it not be about your body size?”

“The amount of mana your body can hold depends on your core size, not your physical size. So a bigger tap means a bigger mug.” She explained.

I put up my hand.

“Koyuki.”

“If our core is a tap, can’t we just cast spells endlessly?”

“This is where magic fatigue comes in. So having a bigger core means you produce more mana, and your body can hold more mana. That means you can cast bigger spells. But using magic makes you tired. Filling your mug to the brim allows for one big spell, but it will exhaust you. Generally speaking, one big spell is more tiring than multiple smaller ones, even if you use the same amount of mana in total. So you can already see one more advantage of having a large core. Not only can you use bigger spells, if needed, but smaller ones will make you less tired.”

Ah. So when I took control of Nyx I used as much mana as I could. So, essentially, I had filled my mug to the brim and then poured it all into the spell. And that was why I had fainted.

“However, your body can be trained. Just like your endurance can improve for physical exercise. In time you will manage more than one big spell before you collapse.”

Someone else had raised their hand.

“Eva.”

“Why don’t we fill our body with mana all the time? Why wait until we want to cast a spell?”

“Two main reasons. First, you can draw mana quickly. So you won’t have an advantage by having mana already in your body. Second, it makes it a lot harder to use the right amount of mana for your spell. When you cast, it’s easier to use all the mana in your body and not just a portion of it. You have much greater control over how much you take from your core. So you pull just the amount you need.”

I had another question and raised my hand.

“Koyuki.”

“Where does the mana come from? What is the tap connected to?”

“The tap is just an analogy. It is believed that your body produces the mana. So far nobody has ever managed to run dry. Mages don’t run out of mana, they just run out of endurance while casting and have to take a break.”

“Helena.”

“How do spellblades work?”

“A good question! First, let’s cover ongoing spells in general. You would think that keeping a spell active would tire you quickly. But most of the fatigue comes from the initial casting. Or from later modifications. Like changing the size of a shield you summoned.”

Victoria looked at me. “Let’s say you control an undead. Raising it and establishing the connection will tire you. Afterwards you won’t really feel it. But your usable core will be slightly smaller as the undead uses part of your mana. If the undead gets destroyed you will have your full core available again.”

She looked at Helena. “Back to your original question. A spellblade has a permanent spell active that enhances their body. Runes are tattooed into the skin to control the magic. They cannot turn those enhancements off. But the magic is not tiring them either. In a way, a spellblade is an artificial magical creature. The downside is, their usable core is vastly reduced. Most spellsblades use half of their core for their runes. The percentage is decided when you become a spellblade and cannot be changed afterwards. It’s a big commitment and you will learn more about them in a class about specialisations.”

It was certainly an interesting path. But I liked the idea of having an undead army. And I would need my mana for that.

After the lesson it was lunchtime. I walked towards the mess hall with Helena. Nyx was sleeping on my head.

“How much mana does it cost you to have Nyx?” Helena asked.

I shrugged. “I am not sure. But it does not feel like a lot. Why?”

“I am just thinking about the size of your future army. Especially since your core will grow even bigger! Hehehe.”

Helena really had a good evil laugh. Maybe I should work on my own?