My idea was simple—mark everyone currently inside the nightclub with a thermal signature.

  Of course, it wouldn't have to be everyone.

  Considering that the severed hand of the Shadow Swap Oddities was a rough male hand, we could first filter out those whose hand shapes didn’t fit the criteria.

  The Oddities must be among the remaining individuals.

  Even if his true body wasn’t inside the nightclub at the moment, it wouldn’t matter.

  Since he had always used his shape-shifting ability to enter and exit the nightclub, there had to be a humanoid clone of his inside.

  If I marked the clone with a thermal signature, I could still track him.

  Once he used his ability to switch pces, I’d immediately know who the real target was.

  However, there might be a problem with this pn.

  After listening to my expnation, Zhu Shi raised an objection: "Wouldn't the Shadow Swap Oddities notice your thermal signature? Since it’s essentially a patch of heat, sticking it onto someone would make it easy for them to detect. Anyone would find it odd if an area of their body suddenly had an abnormal temperature."

  "I can pce the thermal signature inside their internal organs," I replied.

  "The body's internal environment is naturally warm, and it's far less sensitive to minor temperature changes compared to the skin. Normally, it wouldn't be noticed."

  "How do you even know that?" Ma Zao asked curiously.

  "Have you used it on someone before?"

  "Hmm?" Zhu Shi seemed to realize something.

  She gnced at Ma Zao, then at me, and her gaze suddenly turned sharp.

  I quickly changed the subject.

  "But there’s another concern I have about this pn—whether people with supernatural abilities could sense it."

  "...You're right," Zhu Shi temporarily let it slide.

  "If the Shadow Swap Oddities notices it, he might use his shape-shifting ability to transfer the marked causality onto a clone, allowing himself to escape without any burden."

  "Wait, did I misunderstand earlier? Isn't the causality transfer effect of his shadow-swap ability only triggered passively when he suffers a fatal injury?" I immediately asked.

  "You didn't misunderstand. When he actively triggers the ability, it simply swaps his position with a clone. However, we can't rule out the possibility that he might use self-inflicted harm to trigger the passive effect," she replied.

  Although I doubted whether the Shadow Swap Oddities would come up with such a method, being cautious wasn't a bad habit.

  But this posed a major problem—his shadow swap ability was already an absurdly powerful escape technique.

  If he could trigger the causality transfer effect himself, even if we managed to find him, there would be no way to prevent his escape.

  I was considering whether I could tch onto the causality of his true body when he activated his ability to flee.

  If successful, it might even allow us to prevent the shadow swap ability from working altogether.

  However, this idea was purely theoretical at this point, and the success rate was uncertain without practical testing.

  I asked Zhu Shi and Ma Zao if they had any ideas to counter the shadow swap ability.

  Ma Zao looked troubled.

  Zhu Shi, however, presented her own pn: "I've actually thought of a specific tactic. You could first entangle him with your fmes. No matter where he moves, we would be able to track him. Once he realizes that he can't escape from us and falls into complete despair, the ‘Seed of the Heart’ will leave his body.

  "In that state, he should be unable to use his shadow swap ability anymore. At that point, I can interrupt the ‘Seed of the Heart’ from destroying his brain’s information, and we’ll be able to bring his intact head back to Lu Chan. Mission accomplished."

  "Leaving aside whether this method would actually drive him to absolute despair..." I said, "even if I can entangle him with fmes, wouldn't he still be able to use his shadow swap ability to transfer my fmes onto his clone?"

  "The causality transfer effect of his shadow swap ability, when triggered passively, only applies to causes directly reted to his death," she expined.

  "As long as the person delivering the fatal blow isn't you, but rather me or Ma Zao, or if you separate the fmes used for tracking from those used to kill him, the tracking fmes won’t be transferred away automatically."

  I finally understood what she meant.

  Simirly, if he commits suicide because of my thermal marker, the marker will be transferred, since it becomes associated with his death.

  As long as we prevent him from committing suicide with this motive, the thermal marker won't be transferred.

  For me, that shouldn't be difficult.

  Thinking it over carefully, this rule was actually hinted at before.

  Last night, when Ma Zao cut off the Shadow Swap Oddities's hand, and he swapped pces with his clone afterward, the severed hand did not disappear as part of the shadow clone.

  Instead, it remained as actual flesh from his real body.

  This was because the act of cutting off his hand wasn’t sufficiently linked to the fatal injuries he suffered afterward.

  I had essentially grasped the detailed workings of his ability, and at the same time, I was surprised by Zhu Shi's insight.

  She had seen through the Shadow Swap Oddities's ability to such an extent that even he might not understand it as well as she did.

  The power of "Buzhou Mountain" was truly beyond imagination.

  "Zhu Shi, since you can perceive the fws in his ability, can you also disrupt it entirely?"

  I had asked casually, but to my surprise, Zhu Shi hesitated.

  "Huh? You can actually do that?" I was shocked.

  "I can... but only under certain conditions," she said.

  "With my current skill level, I can only disrupt his ability when he activates it, and even then, the effect would only be temporary.

  "Moreover, the activation time of his ability is instantaneous. Catching that precise moment is too difficult for me right now—at best, I have a ten percent chance of success."

  "I think that's already pretty outrageous..." Ma Zao couldn't help but hide behind me.

  Zhu Shi looked visibly hurt. "Hey, wait! Ma Zao, why are you keeping your distance from me?"

  "Let's not focus on that for now. We've at least come up with a way to stop him from escaping, but we still haven't figured out how to identify him," I said.

  "Can I impnt thermal markers on you both? Help me assess whether the Oddities could detect the presence of an added thermal signature."

  Hearing this, Zhu Shi gave me a suspicious look, as if questioning my true intentions, but then said, "Alright... let's give it a try."

  I attempted to impnt thermal markers into their internal organs.

  Zhu Shi paused briefly before giving her response: "I can sense the mana fluctuations from the thermal marker. Your proposed strategy won't work."

  "I can't feel anything at all," Ma Zao, on the other hand, shook her head. "But my opinion can't be taken as a reference. Right now, my soul is still wounded, and my ability to sense mana fluctuations is far weaker than before."

  "I see..." I appeared disappointed on the surface, but inwardly, I let out a sigh of relief.

  Ma Zao's reaction confirmed that my previous attempts to impnt thermal markers inside her body hadn't been exposed.

  "Zhuang Cheng, although you yourself don't produce noticeable mana fluctuations when using your abilities, the fmes you release do. You need to be more careful in the future," Zhu Shi reminded me.

  "Mana fluctuations..."

  Patrol Lu had mentioned this term before as well.

  As the name suggests, it likely refers to the influence generated when using anomalous powers—something that hunters like Zhu Shi can perceive.

  Then, I suddenly realized an issue: "What about my ‘Fireflies’? I sent them into the nightclub earlier—could the Shadow Swap Oddities have detected them?"

  "You don't have to worry about that. The mana fluctuations emitted by your ‘Fireflies’ are incredibly subtle. Even with my keen senses, I can barely detect them. The Oddities is even less likely to notice," she shook her head.

  "Your thermal marker is actually quite discreet as well. If it hadn't entered my body directly, I wouldn't have been able to sense it."

  Previously, I had used my ‘Fireflies’ to eavesdrop on her phone conversations, and she indeed hadn’t noticed at the time.

  However, I had never personally felt these so-called "mana fluctuations."

  This wasn't the right time to ask, but I would have to learn from Zhu Shi ter on how to sense them.

  For now, I needed to focus on the current issue.

  Since impnting thermal markers on everyone in the nightclub was not feasible, I had to reevaluate the previous clues and reconsider who the Shadow Swap Oddities might be.

  Was it necessary to revisit Chang'an's earlier accounts after all?

  According to Ma Zao's suggestion, our unexpected encounter with Chang'an and Jin Yu might contain clues crucial to the core of the incident.

  Could it be that hidden within Chang'an's narrative about their experiences y the key to identifying the true body of the Shadow Swap Oddities?

  Or could it be that the Shadow Swap Oddities is actually one of the “characters” in Chang’an and Jin Yu’s experiences?

  In the events they described, excluding Chang’an and Jin Yu, there were exactly three distinct individuals: Jin Yu’s father, her mother, and the nightclub owner.

  Considering that the Shadow Swap Oddities is inside the nightclub, I initially suspected that it might be the nightclub owner.

  However, this theory was already ruled out by the man in the bck suit.

  The Oddities is the nightclub owner's “partner,” and since the owner is a woman, that coarse male hand clearly couldn’t belong to her.

  By the same logic, Jin Yu’s mother should also be excluded.

  That leaves Jin Yu’s father. Not only is he male, but he also fits the condition of "frequently visiting that nightclub."

  But is it really okay to settle on a target so casually through process of elimination?

  I know Ma Zao’s bad luck is ridiculously effective, but if just wandering around outside could lead us so easily to the key to the mystery, wouldn't that be too absurd?

  If we guess wrong, we might never have another chance to capture the Shadow Swap Oddities.

  I need more evidence...

  I kept pondering over Chang’an and Jin Yu’s experiences.

  Suddenly, I caught a gring inconsistency.

  Why did I overlook this before?

  Even as I marveled at the realization, I felt certain I had finally grasped the true identity of our target.

  "Jin Yu, you mentioned that you decided to join the nightclub to set your father up after hearing that he frequently visited the pce, right?" I turned to Jin Yu.

  "And after that, the owner just treated you like an ordinary employee without giving you any special privileges."

  "Yes..." Jin Yu replied with a puzzled expression.

  "Is there a problem with that?"

  "It’s a masquerade-style nightclub," I said.

  "All the guests wear head coverings, and the staff wear masks. Whether it's for the sake of fun or privacy, the real social identities of the guests are concealed."

  "Then how could you be sure that your father was still visiting the nightclub after you joined?"