Han Xuhan's primary instinctive response to the mental demon's offer was to consider it another sinister scheme. But he was so inexperienced about the world of cultivation that he couldn't determine what exactly this scheme could achieve.
If the demon's intention was to cause him to suffer spiritual damage, Kong Ye would rush over immediately with an unlimited supply of Mindkiller poison the moment it begins. If the demon's goal was a more long-term method of gradual spiritual damage, it wouldn't have much of a potential either considering the tournament would be over by then and he'd return to the original territory of Crimson Snow Sect, where Kong Ye and Xuan Zi could exert an even more stringent control over his movements.
Unless and until the demon left his body, Han Xuhan didn't see any opportunities for it to be freed from their control.
In that sense, he had to discard considering the possibility that this 'spiritual training' was intended to harm his spiritual existence. In the same vein, if this wasn't a scheme, then nobody would be happier than Han Xuhan!
Getting to train his spiritual existence while he was still in the Physique Transformation Realm? How awesome was that?! At least he would no longer be a trash with unremarkable abilities! If he could get past the Physique Transformation realm, he would have a massive advantage over his peers!
No, no, no... He was getting too far ahead of himself. If someone was offering him such benefits, there had to be a hidden catch as well. Cautious, Han Xuhan neither confirmed, nor denied the demon's offer to him. Instead, he used a testing maneuver.
Summoning Tun Shi Tian back to the island, Han Xuhan shouted loudly, "Little Tian, how did it feel, to be such a weakling that you couldn't even hold the gaze of a mere child without going insane?"
"...What are you trying to do?" Tun Shi Tian said in a vigilant tone.
Shit, the birdie had gotten smarter. Han Xuhan could still remember those early days of cultivation when all he needed to do was to call the owl by some nasty nicknames to rile him up.
"I'm trying to guide you, minion!" he declared righteously. "Don't you want to grow stronger, powerful enough to face these ancient beasts and look them right in the eye boldly? Don't you want them to feel true despair when they try, try, and try to pollute your spiritual body, only to fail miserably every time? Don't you want to grow into a truly powerful cultivator who could dominate this primordial Totality?"
Tun Shi Tian considered it for a moment before nodding. "Yeah, I do, but why are you trying to motivate me all of a sudden? Did you stumble upon another risky obstacle that you don't want to deal with yourself?"
From behind, Zhanxian started cackling uncontrollably. Tun Shi Tian harrumphed, realizing that his suspicion had hit the bullseye.
"Tsk~ why so impatient? Can't even let me finish my introduction. Well, you're not wrong. I have a risky method of giving you a massive boost in terms of spiritual capability. Do you want to take the opportunity and start training?" Han Xuhan asked, entirely unabashed.
"As long as my growth is guaranteed, why would I fear risk? I'm not a coward like Zhanxian and you! Bring it on!" Tun Shi Tian roared. "Cowards aren't fit for the grand dao! To tread the path to heaven, we must fight for every opportunity!"
"I'd like to remind you that we've been kicked out of the heavenly domain. Whatever path we're treading, heaven won't be standing at the end of it," Han Xuhan said. "But feel free to yell whatever makes you feel better about it, I suppose. Now, let's begin the training."
From above, the demon's voice floated over.
"I had a feeling that you were going to use your minions as guinea pigs again, and I wasn't disappointed. Are you sure you're not a demon descendent yourself, Xuhan?"
Han Xuhan, Zhanxian, and Hai Yin Zhe stood some distance away from the Tupshu, leaving Tun Shi Tian to face its next attack. They still couldn't look at the Tupshu directly, especially not now when it was about to open one of its numerous eyes and launch a wave of mental attack. So all of their attention was focused on the owl.
"The eye of a Tupshu is its primary hunting weapon. When a prey with an unrefined spiritual body like yours faces this eye, the most common outcome is a burst of mental distress in the form of inexplicable fear, a burst strong enough to freeze your fight or flight response. In fact, once this fear is born, most prey are physically paralyzed for some time in their material world."
Listening to the demon's opening discourse, Tun Shi Tian cocked his head up pridefully.
"Fear? That is a mere instinct. How can I be a cultivator if I am unable to conquer my own instincts? Bring it on!"
"He's a bit too enthusiastic today," Han Xuhan muttered, a bit puzzled.
"It's called self-preservation, master," Zhanxian remarked from his side. "We almost got wiped off this world three times today. Would you be lacking in enthusiasm for training after these ordeals?"
The demon, in the meantime, let out a sinister laugh.
"Good, good, good! That's the attitude I like! Show the world that you're special! That you can conquer one of the biggest hurdles that cripple human cultivators on the Soul Reformation Realm. Take this!"
"Wait, what did you say-"
Tun Shi Tian didn't get to finish the sentence. The demon must have made the Tupshu open its eye. Captured in its predatory stare, the owl's words died in his beak.
Twenty seconds later, Hai Yin Zhe and Zhanxian had to rush forward to restrain a rambling, twitching bird.
"Purple! The world is made up of purple! But there are gaps in the world! There are gaps in us! Help! Help! Where is the rest of me?!"
The screams didn't lessen for a long time. Han Xuhan suggested taking the owl back to the material world, where the influence of the Tupshu might be reduced. But the demon stopped him.
"I didn't stop you from doing so the last time because the bird wasn't even under the full effect of the gaze at that time. Right now, you can completely cut off every bit of connection the owl has to this totality and he still wouldn't recover from the spiritual pollution automatically. This is a struggle he has to deal with himself. Let it happen."
"The last time I let Tun Shi Tian take a mental attack, he stared at the eyes of the Tupshu for about ten seconds. But he didn't show this state of fear and panic that he's showing now," Han Xuhan said. "This time, he held the Tupshu's gaze for twenty seconds and went full nuts. Doesn't that mean there are phases to this mental attack? The intensity is increased with each second, right?"
"Right, and wrong," the demon replied. "Yes, there are stages that you can classify a mental attack into. But the intensity has nothing to do with time. The only aspect of time involved in the attack is the period taken to completely destabilize the mental faculties of the prey. I made this Tupshu release its weakest mental attack. Being an unrefined spiritual body, your minion's first instinctive output was fear. But it will only turn into fear if the attack is completed. So the weakest attack of the Tupshu needed only twenty seconds to elicit the first phase of spiritual pollution inside Tun Shi Tian, which is fear."
"...." Han Xuhan felt like he'd appreciate a head massage by now. Learning new things was nice and all, but when so many new avenues of knowledge got crammed into his day at once, it caused nothing but confusion.
"Why fear, though?" he asked.
"Because fear is the first and most powerful negative emotion etched into human spirit," the demon replied. "It is natural for most humans to show this response before other emotions and instincts when facing spiritual pollution."
"Is there a difference between mental attack and spiritual pollution?" Zhanxian managed to pinpoint a crucial issue out of the blue, startling Xuhan. Indeed, he had been treating both the same, using them interchangeably. Perhaps there was a difference between them? That would clear away some of his confusion.
"There is," the demon answered generously.
"Mental attack is a generalized term. Your mental world encompasses not just this spiritual realm here, but all of your thoughts, consciousness, and memories. Spiritual pollution is a much narrower concept. Only when a mental attack is invasive enough and has the capability to leave permanent damage on your spiritual world can it be called spiritual pollution. Take this instance for example.
When the Tupshu opened its eyes and stared at Tun Shi Tian, that was a mental attack regardless of its effect. But only after twenty seconds, when the attack succeeded in evoking the first phase of spiritual damage, it became an actual spiritual pollution. Now, it's up to the prey to crawl out of the hellhole of hallucinations. Each time he manages to succeed, he'll need less time dealing with the next attack."
"Is it that simple? You said a lot of cultivators are crippled by spiritual pollution in the Soul Reformation realm, right? How can we climb over that hurdle so easily?" Han Xuhan said suspiciously.
"First of all, this training isn't the cultivation procedure of your Soul Reformation realm. Do you think a martial artist with an exceptionally sturdy body is the same as a Physique Transformation realm cultivator? Is his martial art training the same as a cultivator? No! One is driven by qi, the other is purely physical strengthening.
Similarly, cultivation in the Soul Reformation realm is driven by qi, while this training is a purely spiritual strengthening. But it is true that with a stronger body and soul, you'll have an easier time cultivating, and higher potential to reach!"