"Before? Before, I passed through once when I followed him in. I've already forgotten what it felt like..." Duanmu Yu shook her head with a bitter smile. It was hardly her fault. Wei Zhao had been able to detect that faint, almost imperceptible anomaly not entirely because of any exceptional sharpness of perception, but mainly because he had gone back and forth several times over in order to secure a retreat. Duanmu Yu had only done it that once, so naturally she could not have noticed.

Yet even if Wei Zhao had sensed that thread of anomaly, it did him no good, for he could not trace it back to its source. And if the root cause could not be found, then any talk of a countermeasure was even less within reach.

"Let's go. We'll search carefully first and talk after." With that, Wei Zhao took the lead and walked forward, but he had gone only a few steps when he stopped short.

Duanmu Yu was puzzled at the sight, but after one glance at the scene before her, she too was struck dumb. The great tent was still that same great tent; the various props and furnishings differed in no way from the real world. Neither in spatial arrangement nor in any single object was there the slightest anomaly.

And yet it was precisely the absence of any anomaly that was the greatest anomaly of all!

Never forget, Wei Zhao had killed the Water Lily Guardian in this very place. Yet before their eyes there was neither that mutilated corpse nor any wreckage from the aftermath of the true-qi pill-fire bomb—only cleanness, spotless and without a speck of dust.

"This isn't the world in the mirror from before?" Duanmu Yu's expression turned as though she had seen a ghost, and at the same time carried a measure of wishful hope. If this was not the world in the mirror, then could it be the real world?

Whoever found themselves in such a predicament could hardly help harboring a shred of hope, and Wei Zhao was no exception. Unfortunately, after he and Duanmu Yu went out and made a circuit, that shred of hope was shattered at once.

This was not the former world in the mirror, nor was it the real world—but yet another world in the mirror.

Nor was that all. This world in the mirror likewise had no flaw whatsoever, and still the tent-curtain was the one and only entrance and exit.

Back before the tent-curtain once more, Wei Zhao and Duanmu Yu fell silent in unspoken accord. Their situation grew ever more tangled and inexplicable, and ever more impossible to deal with. Not only were both sides worlds in the mirror—the crux was that this world in the mirror was not even the same one as before. What on earth was going on?

After a long while, Duanmu Yu raised her head and looked at Wei Zhao. Though she did not speak her question aloud, it was plain that she was asking him what they should do next.

"Let's keep testing." Wei Zhao gazed thoughtfully at the tent-curtain before him. Since no flaw could be found, there was nothing for it but to grit their teeth and keep experimenting. Only once some pattern had been puzzled out would it be possible to find a way to break the trap.

So saying, Wei Zhao stepped forward to pass through the tent-curtain, but at the last moment he paused. He took out a garment from his jade-pendant space and tossed it on the ground—a girl's dress from the mortal world. Placed in this world in the mirror, it was a unique marker.

Duanmu Yu understood his intent at once. "You want to verify whether this world in the mirror will turn into another one later on?"

"Exactly." Wei Zhao nodded. He already had a bold conjecture, and this garment should, to some degree, serve to corroborate it.

"But a single garment may not prove anything. Why not split up for the time being, and use me, a living person, as the marker? Wouldn't that be more reliable?" Duanmu Yu boldly proposed.

"No." Wei Zhao shook his head decisively, then smiled bitterly as he looked around at this world in the mirror. "If I'm not mistaken, by the time we come back to this place again, this garment will in all likelihood be gone. And if that is so, then once the two of us are separated, it will be well-nigh impossible for us to meet again."

"This..." Duanmu Yu was startled at his words. In a situation like this, the two of them together were far better off than each fighting alone. For her especially, following Wei Zhao still left some slim chance of escaping with her life; but if she were on her own, her chances of survival would truly be faint indeed.

Just as Wei Zhao had predicted, after he led Duanmu Yu through the tent-curtain and back again, the garment he had just dropped was gone without a trace. This was yet another brand-new world in the mirror.

"What exactly have you figured out?" Duanmu Yu could not help asking.

"These last few times passing through the tent-curtain, I think I've come to understand why that lingering sense of anomaly arises." Wei Zhao paused, then suddenly changed tack. "Have you ever looked into a mirror?"

"Of course." Duanmu Yu looked baffled.

"And have you ever looked into two mirrors at once?" Wei Zhao asked again.

"Two mirrors at once?" Duanmu Yu did not grasp it for a moment. Only after Wei Zhao gestured with his hands did understanding dawn: he meant standing between two large mirrors facing each other, so that they reflected one another.

"You mean one mirror can reflect only one world in the mirror, but if there are two mirrors facing each other, they can reflect one another into countless worlds in the mirror?" Duanmu Yu grasped it at a word. Wei Zhao's conjecture fit their present predicament quite well—apart from this possibility, nothing else could explain it.

"Correct. That is the source of the anomaly I mentioned. When I first confirmed our retreat, I was crossing back and forth between the real world and the world in the mirror. Now, however, I am crossing between two worlds in the mirror. The two are not the same." Wei Zhao explained.

"The difference must be infinitesimal. Your perception is truly that keen?" Duanmu Yu was astonished. She had not tested it repeatedly as Wei Zhao had, but she still remembered the general feel of it. Even if there was a difference between the two, it could at most have been one part in a thousand, or even one in ten thousand. That Wei Zhao could precisely catch even this, and from it reverse-engineer the conjecture of two mirrors—such insight was simply inconceivable.

"I'm a primal spirit. If I didn't even have this much perception, wouldn't I be worthless?" Wei Zhao smiled.

"But I still have a question. If it really is two mirrors as you say, why is its corpse gone, and why is the garment you just dropped gone too?" Duanmu Yu asked with a frown.

Two mirrors could indeed explain the origin of these worlds in the mirror, but this point still could not be explained. If these worlds in the mirror were reflecting one another, then in theory, so long as any one of them changed, all the others should change along with it—they should not remain unmoved.

"No, you misunderstand. The entity reflected by these two mirrors is only one—the real world outside."