"'Heat it?' Jon hesitated, then answered without thinking. "After processing, the Ashwinder egg mixed with the Murtlap tumor solution is supposed to be slowly heated until the shell softens, then the shell is crushed—"
"No open flame!"
Horace Slughorn nearly roared. "These are Ashwinder eggs—extremely sensitive phlogiston by nature! And after being treated with Gubraithian Fire, even the tiniest spark can send them into complete combustion! Merlin's beard—one fully combusted Ashwinder egg releases enough heat to burn my castle down ten times over!"
"Sorry! Sorry!" Jon apologized at once, hurriedly drawing his wand to extinguish the flames beneath the cauldron.
He knew all too well how much energy an Ashwinder egg contained—after all, he had used one personally before.
Slughorn, still keyed up, took several minutes before he finally managed to calm down.
"Such a rookie mistake…" He turned back, fixing Jon with a suspicious look. "You weren't… completely unprepared… This is your first time brewing Felix Felicis, isn't it?"
"Y-you figured it out," Jon said, lowering his head in embarrassment. He quickly added, "But I'm very familiar with the specific steps and the potion sequence."
Slughorn looked as though he was about to faint. If it weren't for the Unbreakable Vow, he would have thrown this wretched boy out immediately—preferably as far away as possible.
The opening stages of brewing Felix Felicis were incredibly dangerous. The slightest mistake could spark a massive fire, turning everything within hundreds of meters into scorched earth. Thirty years ago, when Slughorn brewed Felix Felicis for the first time, he had rehearsed the entire process hundreds of times, memorizing every step before daring to attempt it for real. And in the thirty years since, he had only brewed it seven times in total.
And yet this reckless boy actually dared to—
If an accident happened… Slughorn himself would naturally be safe as a wizard. But the castle wasn't magical. If it were reduced to ashes, how could he ever face the ancestors of the Slughorn family?
"It's fine, I swear—I won't make another mistake like that," Jon vowed repeatedly.
"Don't worry, Professor Slughorn," Mrs. Greengrass added from the side, offering words that sounded reassuring but somehow weren't. "If anything unexpected happens, I'll protect you in time. I won't let either of you be hurt."
Slughorn took a deep breath, then let out a helpless sigh. He truly had no choice.
Because of the Unbreakable Vow, stopping the boy beside him from continuing the brew would mean breaking the oath—and the consequences of that were far worse than losing the wager.
On one hand, he had to keep the gamble going until one side failed and it ended. On the other, he had to prevent this boy from making another rookie mistake and blowing up the entire Slughorn Manor.
All he felt was exhaustion.
...
"You must use a lead rod to grind the eggshells! Even the slightest spark will spell disaster!"
"Watch the temperature during the water bath—control it carefully, absolutely carefully!"
"Hurry, add a section of Devil's Snare vine to stop the phlogiston from spreading, or we're in trouble!"
Horace Slughorn's shrill voice rang out from the room again and again.
Clearly, he had repeatedly stopped Jon from turning his entire castle into ashes.
Jon worked at an extremely slow pace. His first mistake really had been caused by inexperience, but the many "mistakes" that followed were quite deliberate. He was drawing Slughorn's attention, forcing him to spend time "helping" instead of focusing fully on his own potion.
There was no other option. Outmatched in skill, Jon could only resort to this slightly underhanded tactic to narrow the gap between them.
Thanks to his cautious handling—and Slughorn's constant "assistance" at his side—Jon managed to pass each dangerous step of the brewing process safely.
Nearly six hours later—
Over the next six hours, Jon had finished grinding the Ashwinder eggshells. The warm water bath fused the shell with the solution, after which he gradually added Devil's Snare vines to neutralize the phlogiston. Finally, when he stirred in a small spoonful of finely powdered white sugar, the liquid in the cauldron completely calmed, becoming a clear solution.
Slughorn couldn't help but let out a breath of relief.
Once this step was complete, the solution stabilized entirely. The castle was no longer at risk of being blown apart.
...
"You really are an impressive young man," Slughorn said despite himself. "To reach this stage on your first attempt—back when I was young, I doubt I could have managed as much."
As he spoke, he lowered his head and refocused on his own cauldron.
Slughorn had actually completed this stage over an hour earlier. However, with so much of his attention diverted by Jon, the potion he brewed this time was noticeably worse than his previous results.
Even so, it was still far superior to the solution Jon had just produced.
"Thank you," Jon said solemnly, nodding.
"Do you need a break?" Slughorn asked with a smile, already convinced the outcome was decided.
"No need," Jon replied calmly. "Let's continue."
From this point onward, their brewing steps diverged, as each followed a different potion sequence.
Slughorn went first, taking a bottle of thyme tincture from the shelf and dripping three drops into the clear liquid in his cauldron. Jon also rummaged through the shelves, but he took out a bottle of thyme phenol instead. He added only a single drop to his potion, then sprinkled in a small amount of powdered white sugar.
Watching his movements, Slughorn frowned slightly.
"Are you related to the late Hogwarts Headmaster, Armando Dumbledore?" he asked quietly.
"Headmaster Dumbledore… uh…" Jon replied evasively. "A little, I suppose… My great-aunt and he… well…"
"Merlin help us!" For the first time, Slughorn's expression turned serious, a hint of alarm flashing across his face. "You're using Headmaster Dumbledore's Felix Felicis sequence…"
He quickly strode to the ingredients shelf and began selecting the required materials at speed.