To make the Philosopher's Stone, the most important material is the ashes left behind after a Phoenix's Nirvana, Kael had known this for a long time, after all, the current Philosopher's Stone has his contribution.
However, what Kael didn't anticipate was that repairing it would also require this material.
"I no longer have any Phoenix Nirvana ashes," Kael said, "I only took half last time, and all of it went to you. The remaining half is with Snape, and it has been turned into Phoenix Potion."
"I know." Nicolas nodded, "But Dumbledore's Phoenix is with you, right?"
"What's the use of that?" Kael asked, "Didn't you say before that you must use ashes left after a natural Phoenix Nirvana to make a Philosopher's Stone? It's only been a few years since Fawkes' last Nirvana, we can't just keep waiting, can we?"
Kael was unsure how long it would take for a Phoenix to naturally undergo Nirvana again, but he could be certain that this interval was definitely not short. If it underwent Nirvana every few years, the ashes left behind wouldn't be so precious.
"Oh, you've misunderstood." Nicolas looked at Kael, "When making a Philosopher's Stone, there are indeed strict requirements for the materials, but if it's just repairing, the restrictions aren't as severe. Any ashes will do; it doesn't necessarily have to be from natural Nirvana."
"Well..." Kael suddenly looked hesitant.
Despite being aware that undergoing Nirvana once wasn't a big deal for Fawkes, merely leading to a period of weakness, after a few months he would recover.
Being weak for a few months in exchange for saving Dumbledore seemed like a worthwhile trade.
But for some reason, possibly due to some strange psychological influence, Kael was deeply resistant to making this decision, and didn't know how to explain it to Fawkes.
Nicolas noticed Kael's hesitation but did not urge him, simply stating calmly, "No need to decide now, you have two weeks to consider. After two weeks, I will complete the process of rewriting the Magic Text, and then it will be time for the Philosopher's Stone..."
Nicolas waved his hand, preparing to send Kael out.
But at that moment, a golden-red figure appeared in mid-air, Fawkes landed on Kael's shoulder, rubbing his ear with the feathers on its head.
"Did you hear everything?" Kael asked.
Fawkes nodded.
"Then decide for yourself." Kael sighed, "If you don't want to, we can think of other ways... like asking Newt or checking Professor Dumbledore's vault."
Fawkes didn't speak, just flew to the nearby table, all its feathers vibrating, transforming instantly into a fiercely burning fireball.
The fireball was very bright, but had no temperature, and didn't affect the wooden table at all.
"Now, you don't need to worry anymore," Nicolas said.
"Yes." Kael nodded, Fawkes' decision indeed brought him a sigh of relief.
After that, neither spoke again. Nicolas used a camera-like device to record the entire process of Fawkes' Nirvana.
The time wasn't long, just a few seconds. Once the flames extinguished, only a heap of deep brown ashes remained on the table, followed by a featherless chick poking its head out from the ashes.
Kael reached out, cradling it.
"Fawkes, you really look ugly right now," he couldn't help but say.
No matter how many times he witnessed it, a just reborn Phoenix looked extremely ugly, featherless was one thing, but all wrinkly too, resembling a miniature Shar-Pei.
Fawkes gathered all its strength, using its young beak to peck forcefully at Kael's finger.
But given Fawkes' current state, this degree of attack was entirely painless to Kael.
Kael placed it on a velvet cushion inside a box, surrounding it with herbs... all very precious herbs, Mandrake Leaf, Cloak Grass, Shrunken Wrinkled Fig Rootstock, and so on, to help Fawkes quickly restore its vitality.
"Shaqiel." He advised the eager Zouwu nearby, "Don't get close to it, otherwise you'll get beaten later, and I won't be able to persuade it."
The Zouwu stepped back slightly, then disdainfully raised its head, elegantly leaping onto the nearby bookshelf, its long tail hanging above Fawkes' head, swaying back and forth.
Kael noticed that Fawkes seemed not to mind, so paid it no heed.
After finishing all this, he left the box and turned his attention to the pile of ashes on the table, which Nicolas had already collected into a bottle.
"The quality isn't great, but it's barely usable."
He handed over the bottle, Kael took it, immediately noting the difference.
The previous bottle of ashes he'd obtained was very beautiful; at first glance it was black, but as long as it faced sunlight, countless dazzling golden sparkles could be seen hidden within the black.
But these ashes in front of him were only black, Kael rotated the bottle for quite a while before faintly seeing a shimmer, like the night sky in London, where all starlight was obscured completely.
"Doesn't this affect usage?" Kael asked.
"Don't worry, the core of the Philosopher's Stone remains," Nicolas explained, "Now we just need to get it working again."
"Just a moment." Nicolas turned, taking another cauldron from the shelf behind him.
This cauldron was much smaller, only about the size of a fist, resembling a child's toy, but inside it also contained potion, a shiny pink one.