They came back to the house with the darker foundation stones two days later, this time with a shovel Old Han had lent them without asking too many questions about what they wanted it for.
"You're sure about this?" Mei Lin asked, watching Xu Yuan test the ground near the foundation with the flat of the blade.
"No. But it's the only new thread we've got, and I'd rather follow it than sit still."
The digging was slow. The ground here was harder than the fields back in Pinebrook, packed tight by however many years had passed since anyone last disturbed it, and Xu Yuan's arms ached within the first twenty minutes in a way that had nothing to do with swordsmanship. Mei Lin took turns with him, refusing to just stand aside and watch, and between the two of them they cleared a shallow trench along the base of the wall within the hour.
It was Mei Lin who found it — a flat stone, smaller than the foundation blocks around it, set into the wall at an angle that made it look, at first glance, like just another piece of the structure.
"This isn't load-bearing," she said, running her fingers along its edge. "Look how it sits. Everything around it is set flush. This one's got a gap all along one side."
Xu Yuan crouched beside her and worked his fingers into the gap. The stone gave, reluctantly, after a long moment of pressure, sliding free with a grinding sound that felt too loud in the quiet ruins.
Behind it was a hollow space, no bigger than a small chest, empty except for a single object resting in the dust — a flat disc of dark metal, unmarked by rust despite what had to be centuries underground, etched with a spiral pattern that curled inward toward a center too fine to make out clearly in the low light.
Neither of them touched it right away.
"Is it safe?" Mei Lin asked.
"I don't know." Xu Yuan studied it without reaching for it. "Nothing about this place has felt safe since I first found it. But nothing's tried to hurt me for looking, either."
He reached in slowly and lifted the disc free. It was heavier than its size suggested, cool against his palm despite the warm afternoon, and the moment his fingers closed fully around it, the pale screen unfolded itself in the air without being summoned.
Artifact Detected
Recognition Insufficient
The same message as always. He waited, in case something more followed. Nothing did.
"What does it say?" Mei Lin asked, unable to see the screen herself.
"Same as the monument. Not enough recognition yet." He turned the disc over in his hand. The back was smooth, unmarked, nothing like the busy spiral on the front. "Whatever this is, the Interface knows it's important. It just won't tell me why until I've earned it."
Mei Lin studied the spiral pattern over his shoulder. "It looks like water. The way it curls."
Xu Yuan looked again, and she was right — the pattern didn't look carved so much as captured, like someone had frozen a whirlpool mid-motion and pressed the shape into metal. "Or wind. Or smoke."
"Or nothing at all, and we're just looking for shapes because we want there to be one." She said it lightly, but there was real caution underneath it. "You should be careful with that. Whatever hollowed out this village might have left it behind on purpose."
"I've thought about that." He wrapped the disc carefully in a strip of cloth from his pack rather than putting it directly against his skin. "But I don't think it was left as bait. Someone hid this. Sealed it behind a stone that wasn't meant to look like anything but wall. That's not how you leave something for an enemy to find. That's how you protect something from one."
Mei Lin considered that. "Protect it from what took the village?"
"Maybe. Or protect it for whoever came looking afterward." He looked at her. "Maybe for whoever eventually figured out where to dig."
They filled the trench back in before the light faded, more out of instinct than any clear plan — neither of them wanted to leave an obvious sign that something had been disturbed here, not with Gu Chen's scouts combing the wider region and a registrar from the Capital cataloguing every ruin they found.
On the walk back, Mei Lin was quieter than usual, glancing at the wrapped disc in Xu Yuan's pack more than once.
"You're going to tell the Chief about this."
"Eventually. Not yet."
"Why not yet?"
Xu Yuan thought about Old Han's reasoning from days earlier, the half-truth he'd refused to hand over because he didn't trust it enough himself. "Because I don't know what it is yet, and I'd rather bring him something solid than a guess dressed up as an answer. If I hand him a mystery and he starts making decisions based on my guesses, and I'm wrong, that's worse than saying nothing at all."
Mei Lin walked beside him a while before answering. "That's the same thing Old Han's doing to you, isn't it. Waiting until he trusts what he knows."
"I didn't think about it that way. But yes. I suppose it is."
"Does that bother you? Doing the same thing to the Chief that frustrated you when Old Han did it to you?"
Xu Yuan considered the question honestly instead of brushing past it. "A little. But I think it's the right kind of frustrating. The kind that means everyone's actually being careful instead of reckless."
Mei Lin nodded slowly, accepting that, though the look she gave him said she'd remember this conversation the next time she was the one holding a secret worth keeping.