Li Yan and Li Jiuchen approached the Wordless Bluestone Slab from opposite directions, more or less facing each other. Not only did the slab bear no writing, it also lacked the spirit patterns carved into the surrounding cave walls. It felt like the cleanest spot in the entire cavern.
Li Yan stopped about three feet from the Wordless Bluestone Slab. On its other side, Li Jiuchen stopped roughly three or four feet away as well.
Li Yan did not release his Divine Sense. Standing there, he merely examined it from top to bottom with his eyes. The Wordless Bluestone Slab stood planted directly in the ground at the center of the cavern, without any stone pedestal, like a gravestone...
The slab was approximately twenty-seven feet tall and half a foot thick. An Ancient Bronze Spirit Lamp rested at the exact center of its top edge. The lamp was the size of an adult's fist, with a lone wick protruding from it, unlit.
Shortly after looking it over, Li Yan's gaze settled on the base of the Spirit Lamp. A line of tiny, fly-head-sized characters in ancient seal script was engraved there. Focusing his eyes, he made out the inscription.
"To open this door, the Heart Lamp must burn. Neither fire nor spirit, only 'harmony' may kindle it."
Li Yan looked around but saw no doorway. It must have been concealed. He then sensed the spirit liquid inside the lamp atop the Wordless Bluestone Slab, before turning his gaze toward the four Spirit Lamps in the corners of the cavern.
There were no lines of tiny writing on the bases of those lamps. Each bore only a single character: "metal," "wood," "water," or "fire"!
After sweeping his gaze over them one by one, Li Yan looked back at the lamp atop