The materials were probably all of the types that were easy to mix into ink, as Xie Yi felt no resistance at all. It was even easier than putting salt into water.
He stirred for a while, then looked up at Shi Yue who held a blank sheet of rough paper out for him.
“You can draw the array unto this. Here, that is what you have to copy. Take it slow and try not to make any mistakes”, he explained, pointing to one of the open tables.
With high expectations, Xie Yi copied the very simple array, trying his best to not read what it would do so he wouldn’t spoil his surprise. The ink dried instantly on the paper, so not more than a few minutes passed until everything was prepared.
“I’ll activate it for you, so that we don't waste cores. Usually, this type of smaller array can be activated by using the core of a spiritual beast and placing it into this middle part here. The array works until the core is wasted.”
Instead, Shi Yue placed a paper-man into the middle and then one of his fingers at the edge of the paper. The array lit up slowly, the lines beginning to glow towards the middle.
The paper figure twitched, then moved.
Xie Yi laughed in delight.
A tiny, flat paper-man was standing up and bowing, then beginning to walk around its array and test the walls. Finally, it took on a grumpy pose as if glaring at Xie Yi before dancing around.
The array could call low-level elemental spirits into a vessel for some time, lightly confining them. The confinement was never binding or lasting, and the spirits only played along as long as they felt like it. Even if Shi Yue kept the array running, the spirit would leave after some time, breaking the bonds by itself or summoning help.
It was stupid, but Xie Yi giggled happily at the sight of the playing paper-man. When it waved to him, he waved back, and only then did the array stop glowing.
“Another one!”, he shouted, giddy. “Another one, another one! Please?”
Shi Yue sighed mentally. Thank god, it had been a good idea, after all.
At his consent, Xie Yi ran right off to prepare the next ink, fidgeting as he waited for Shi Yue to fetch him the paper and array-template. The paper was quite a bit larger this time; as large as his table.
Xie Yi already guessed that this might mean it was an array that would affect himself, and the bits and pieces he read without wanting to had confirmed his guess.
“Am I supposed to stand in the middle?”, he asked anyway, even though he was already in the process of placing the array on the ground, anyway.
“Yes, but-”, Shi Yue started, then went behind the desk and came back with a large blanket. “You will have to take off your robes. Bundle yourself up in the blanket.”
“Am I gonna turn into something?”, Xie Yi guessed with a squeak. His elders had forbidden him from using those types of arrays, but he had always wanted to try. You can turn into animals with them, even something in the likeness of spiritual beasts, or turn your skin to paper, for example. Nothing that would greatly enhance your abilities, but once again, it was a fun thing to play around with.
Shi Yue didn’t spoil the effect but held the blanket around him until Xie Yi had placed his clothes to the side and could take it himself.
This time, Shi Yue didn’t touch the array but activated it remotely, stepping back a bit and watching carefully in case Xie Yi got a shock.
The result was a bit… unexpected.
Xie Yi felt his body bubble, then pull. It wasn’t overly comfortable but not too bad. He held the blanket tightly, fighting against the dizziness, before blinking and looking down.
Taller, much taller than before, a completely different eyesight. Stretching out a hand from inside the blanket, Xie Yi recognized the look of his fingers he was most familiar with.
He giggled again, beaming at his master. “Ehehe! Look, Shi Yue, I’m an adult!”
Shi Yue blinked, quietly, even forgetting to correct Xie Yi. Then the array suddenly stopped and his body formed back into a child’s.
Disappointed, Xie Yi pursed his lips. “Aw!”
He really did like his adult form better… It was too bad that the array had limited space, or he could play around with it. No, actually, he could surely make that portable? Even if it wasn't suitable for it, he could try to tinker around, maybe. That would be nice. Focusing on the array under his feet, he now took the moment to memorize it.
Shi Yue, on the other hand, was rubbing his temples.
God beware. God beware that anyone else saw that. Although -... it would be a disaster anyway. How old was he? It would only be a few years. Good gracious.
There were people who were like foxes, seductively tempting you. Then there were the innocent types that made you want to protect, or the beauties that you just wanted to adore.
Shi Yue was no foreigner to attractive people and while he had kept his fingers off them ever since becoming a master, that didn’t mean that he didn’t have his fair share of experiences from before that.
What could you even say?
That the adult version of Xie Yi made you want to drag him right off to the bedroom while at the same time spoil him lovingly so that no bad things would ever trouble him?
The look of devotion towards Shi Yue was there even in his usual child form, that was true, but coupled with an adult body, it felt like being corrupted. As if tempted to the dark side.
No matter whether Xie Yi would become his disciple or not, he had to make sure that in the following years, Xie Yi would be strong enough to protect himself from all those that would come to court him.
...Such were Shi Yue’s troubled thoughts at feeling so terribly tempted at the sight of the innocent youth clothed in nothing but a blanket before him.
Little did he think about the fact that he, himself, was just as attractive to other people.
Little did he know that Xie Yi had zero interest of showing such an adorable, defenseless face to anyone other than his master, and that he would be almost a bit too good at getting rid of unwanted suitors.
Xie Yi didn’t notice his master’s dilemma at all. He had placed his robes back on and already finished the next ink, waiting in front of Shi Yue with sparkling eyes. Towards the murderous leader of the Demonic Sect, only very few had ever dared to take an interest, and those had been turned into bloody puddles before having the chance to act on it. Even at several hundred years of age... Xie Yi didn't have the slightest idea about how he looked in other people's eyes.
Just like that, they played around for a good hour, also doing things like turning ice into a gelatinous form, turning a leaf as sharp as a knife, or creating a space in which everything up to a certain weight and size could hover.
The mostly useless tricks were even funnier than Xie Yi had expected at first, so he planned to ask Shi Yue for all of them at some other date. He had never been allowed to learn things that wouldn't help him with fighting, so just not having to fully concentrate on a task but just go by feeling was quite nice.
Finally, Shi Yue decided that they had played enough and he put everything away, tapping unto a table to ask Xie Yi to sit.
“Now, let’s work through what we just did…”
He began to explain the uses of arrays, their history, and how they could be read. It was all just basics and nothing that Xie Yi didn’t know about, but his master’s voice was nice to listen to, so he didn’t mind.
When Shi Yue did the loop to needing energy to activate arrays, Xie Yi guessed that they had reached the practical part of the lesson.
Under normal circumstances, this was about trying to feel the particles surrounding you. That alone took about a full day of training for normal students, after that it would be about moving them and finally pulling them into your body. Shi Yue explained it all, then intended to let Xie Yi try so he could explain the difficulties of doing it and slowly guide him through the process.
A very, certainly quite long, absolutely not fast five minutes later, Xie Yi was waving his legs over the ground again, grinning broadly, the circular motion of the particles around his body - slowly moving towards his body in a swirl - anything other than forced or troubled.
Shi Yue awkwardly looked down at him.
“...Did you have someone teach you about cultivation before this?”
“No.” Before, as in, right before this? In his last life, yes, but even then it was later in the timeline.
“Did you… read some sort of book? Find some strange items?”
“No, don’t think so.”
“This is your first time doing it?”
Xie Yi tilted his head and hummed. He was having trouble on how to answer, considering that he wouldn't want to lie but things were so messy with being sent back in time! Well, a few months ago, he had tried to do the practice at Feng Yan's place... “Hm, I tried before, but it made me too exhausted.”
“...How did you know how to do it?”
“From the explanation?” Not Shi Yue’s, but his elders, though the situation was similar. It wasn’t a lie, just… a phrasing that would be easily misunderstood.
Shi Yue turned to look out of the window. Alright, the child was abnormal. No way around it.
The cultivator was struck with the desire to settle Xie Yi somewhere where he didn’t have to worry about other people badly influencing him. If he had this talent everywhere, the boy would be hunted.
Great. Not even his disciple yet, and he already was worrying about others going for the child's body and talent.