After Linjos delivered both the magically sealed dimensional box and the coded letter, Lith felt like a burden had been lifted from his chest. It was the biggest, yet just one among many.

Now he had to prepare for the next dimensional magic exercise, research the runes sealing the boxes hidden inside his pocket dimension with the library's help, study their pseudo core with Invigoration, and find the time to use Accumulation to keep refining his core.

Now that he had finally overcame the bottleneck, he could use his first breathing technique again, to amass the world energy and strive for the blue mana core.

Worst case scenario, it would make him as powerful as the Headmaster or a Professor. Lith had not missed how the more he refined his core, the more dramatic changes he experienced.

At the beginning, Lith had thought that by absorbing the world energy, he was simply overcoming his natural lack of magical force. But over time, by expelling the impurities accumulated in his blood, organs and now in his bones, things had become unsettling even for him.

So many things didn't add up. At the White Griffon academy, there were plenty of students with a mana core stronger than his own, even his teammates. Yet none of them exhibited a physical prowess like the one Lith now possessed.

Hence, it wasn't just a matter of the mana core. As for the impurities, it couldn't be as simple as that. In the past he had removed them with Invigoration from his parents and sisters, but again, no such thing had happened.

Science could not help him; it was clearly related to the different biology of the new world. And then there was how Kalla had reacted to his last metamorphosis, saying that his smell had become less human.

Lith had so many things to do or think about, that his headache started getting worse again, reminding him that first of all he had to sleep. His vision blurred, while his knees became so weak that he had to lean against a wall to keep standing.

"Are you alright?" Yurial asked.

"Not really. I think the fatigue from the fight in the forest is about to kick in. I don't know how long I can hold on."

A sudden pang made him fall on his knees, holding his temples between the hands, trying to withstand the blinding pain.

He had yet to express his gratitude for their help, but the only thing Lith could do was getting back to his room with the help of his friends, falling asleep as soon his head touched the pillow.

The next morning, not even the breakfast gong managed to woke him up. In the end, Yurial had to bang on his door for several minutes before Lith managed to crawl out of the bed.

"Is that a wand in your pants, or are you just happy to see me?" He said with a cheerful smile.

"What the heck is happening? Has the civil war already started?" As soon he managed to regain his senses, Lith realized it was already morning.

"I was about to call for help and have the door kicked down. Yesterday you almost fainted. How do you feel now?"

"Tired." Despite the full night of sleep, he was still very weak. Invigoration still had no effect.

- "Solus, why you didn't wake me up?"

"I tried multiple times, but your consciousness was beyond my reach. Besides, I think you still need plenty of rest." She sounded really worried.

"Why do you say so?" Lith asked.

"Because while you were sleeping, your body kept syphoning the world energy non-stop. Your mana core is still half empty.

It seems that overcoming the bottleneck caused such radical changes to almost deplete your system. Whatever happened this time, you still need time to adapt.

Despite his weakness, Lith decided to continue his day as normal. At every meal he ate more than Quylla, feeling like his stomach had turned into a bottomless pit.

During dimensional magic practice, he discovered that his mana sensitivity was still crude, but his mana efficiency had gone up a notch. Magic flowed freely through him, encountering no resistance.

Casting any spell now required less mana, reducing the burden that such powerful energies exerted on his body. Sadly, that was still not enough.

Even training under Quylla's guidance, making any progress was a real struggle. Usually Lith would compensate his lack of talent with all-nighters and endless energy from Invigoration, but this time he lacked both.

When he was too tired to continue, he went straight to bed, asking his friends to wake him up at all costs, in case he couldn't manage on his own.

The following day, Lith woke up full of energy, his body was light like a feather and his head was finally clear. Both Invigoration and Accumulation seemed to work as normal.

- "Luckily, I contacted the Marchioness before going to sleep, otherwise I would have lost a lot of time. Seems that the refining process now needs a lot of preparation. If I stepped in a new stage during an exam, or worse, after a fight, I would be as good as dead."

During breakfast, the whole canteen was shocked by the latest news. Everyone was discussing the mysterious explosion happened in Kandria that had killed Professor Reflaar, the Master Alchemy teacher.

At those words, Lith almost choked on his food.

"Isn't Kandria the city from which the mercenary team received both the hunting and the delivery mission?" Lith pointed out to the others with a whisper.

"Yeah, it's too odd to just be a coincidence." Friya said.

"Do you think that Professor Reflaar died trying to protect the academy, or because he was part of the conspiracy too?" Phloria's question was on point. Based on what they knew, even professors were untrustworthy.

- "He was a good man. I can't believe he would have brought any harm on his students." Solus refused even to consider the idea of Reflaar being a traitor. "He was an alchemist, and that was an alchemy shop. Maybe he was just in the wrong place at the wrong time."

"I believe you. I'm really sorry for your loss." Lith replied.

Losing one own's first crush so abruptly was never easy, so instead of expressing his usual doubts and paranoia, Lith decided to let her grieve in peace. Even if they had never directly talked, Lith knew how much Solus had valued his company and enthusiasm.

Lith's group kept discussing all the possible implications the explosion could have, and who were the professors more likely to be a traitor. It goes without saying that Professor Rudd was on everyone's top of the list.

Once in the Dimensional Magic training hall, everyone took his place. This time, knowing that Professor Rudd would not give any pointers, Lith positioned himself right beside Quylla, to be able to both learn by imitation and asking her for help.

Only twelve students had to execute the second exercise, Pilfer. All the others were still stuck at the Loop spell.

Pilfer consisted in creating a dimensional door big enough to let the hand slip in and emerge above a table full of quills. Unlike the Loop spell, the students had now not only to open a bigger passage, but also to regulate the distance on their own.

"Begin!" Professor Rudd's voice roared even before the last gong signalled the start of the lesson.

Lith struggled with Pilfer from the first seconds, that soon turned into minutes and then in a whole hour. In all that time, he had made no progress. The only Gates he had managed to generate were all too narrow for his hand to pass, not to mention their exit was still too far from the table.

Quylla was faring way better, her Gates were almost of the right size and distance, but still unstable, disappearing within seconds with a loud bang. She tried to explain what Lith was doing wrong, but what was simple for her was a mystery to him.

Soon the air filled with the bangs from the students' unstable Gates and their curse words, tired of failing while Professor Rudd would only laugh in the face of any plea for help.

Suddenly, a bang resounded louder than ever, soon followed by another and then still another, until Lith started to think that the training hall had suddenly turned into a firing range.

"What in the gods' names is happening!" Professor Rudd's voice had no trace of hilarity anymore.

The space around the students was filled with cracks, small black holes formed and dissolved, causing the bangs that they had just heard. A student curious enough, tried to touch the cracked space, resulting in it exploding with the strength of a grenade.

Professor Rudd managed to save him, Blinking both of them out of the danger zone.

"Everyone, stop casting if you want to live!" He yelled on the top of his lungs. "Somehow the Hall's protections have been turned off."