172: Chapter 172 Array Base Modification, Early Warning System Initially Established (2)

"Four pieces—is that enough?"

"Four pieces are enough to cover the direction of the Dragon Burial Trench." The Old Formation Master stood up from beside the stone disk. There was a brief pause in his knees as he stood—they had gone stiff from squatting too long. "But the sensing array pieces are only the capture end—they also need a receiving end. The receiving end must be connected to the island's spiritual power hub—ideally, it should be connected to the boundary suppression stele. The boundary suppression stele is the root of the entire island's spiritual power circulation—reading the sensing signals from the boundary suppression stele ensures the signals won't be distorted."

Su Qingli tucked the Spirit Stone piece into the cuff of her work robe. She stood up from beside the stone disk—then walked over to the boundary suppression stele. The Array Patterns on the boundary suppression stele were still pulsing at a cycle of ten breaths—blue light climbed from the base of the stone pillar to the top, extinguished after reaching the top, and started again from the bottom. She pressed one hand against the boundary suppression stele—the moment her palm touched the surface of the stone pillar, the pulse cycle of the blue light changed from ten breaths to eight. The boundary suppression stele was responding to her Spiritual Pressure.

"I will start drawing the array path for the receiving end today." She pulled the thinnest array brush from her sleeve. The tip of the brush was almost invisible in the morning light—only by getting close could one see the extremely thin layer of spirit sand powder clinging to the tip.

The Old Formation Master glanced at her—his gaze fixed on the hand holding the array brush. The finger joints protruded slightly while gripping the brush—it was a hand that had long been used to holding an array brush to draw Array Patterns. Array ink was embedded in the nail beds—the black array ink formed extremely fine black lines within them.

"Who did you learn Formations from?"

"I taught myself." Su Qingli twirled the array brush on her fingertips—the movement was light, and the tip drew an extremely fine arc on her finger pad. The arc left a fleeting pale golden afterglow on her finger pad—the pattern of the afterglow matched the path of the Array Patterns of the Geng Metal Sword Intent Killing Array on the reef wall. "Later, I practiced through actual combat—the temporary live lines on Xuangui Island, the third-phase Killing Array on Blue Moon Island, and the cold jade clam farming Formation in the Outer Port's cold water layer."

The Old Formation Master did not continue asking. He picked up the array ruler from the stone disk—and tucked it back into his sleeve. Then, he pulled a folded piece of beast skin from his robes—the beast skin was his own hand-drawn array diagram. The diagram depicted a complete path for the sensing array's receiving end—the connection method for all intermediate array nodes between the sensing array pieces and the boundary suppression stele. He spread the diagram out—pressing it onto the stone disk.

"This path for the receiving end—it's the Ministry of War's standard configuration. I modified the path of the third intermediate node—I changed the straight connection to an arc. The arc can filter out the natural spiritual power fluctuations of waves and tides—leaving only the spiritual power fluctuations of living creatures."

Su Qingli lowered her head to look at the array diagram. She studied it for about ten breaths—then traced a line on the diagram with her finger from the first array node to the last. Her finger reached the modified third node—and stopped.

"The curvature of the arc—did you calculate it based on the curvature of the Blue Moon Island's earth veins?"

"Based on the curvature of that eastern branch of yours." The Old Formation Master tucked the array ruler into his sleeve. "The earth vein direction you marked on the stone disk earlier—the segment of the eastern branch from the Ring Reef to the Dragon Burial Trench has a curvature of about four degrees of deflection every hundred zhang. I modified the arc according to this curvature—the sensing signal won't attenuate as it travels along the arc."

Su Qingli put the array diagram away—tucking it into the inner pocket of her work robe. Then she walked away from the boundary suppression stele—and went to the entrance of the stone chamber. From the entrance, one could see the sea surface in the direction of the Outer Port—the morning light had already blanketed the entire Outer Port. On the reef wall at the easternmost end of the outside of the Ring Reef—the people from the Sin Battalion were moving installation tools for the sensing array pieces up. Commander Cai stood on top of the reef wall—clutching a sketch of the installation positions that Su Qingli had just drawn.

That afternoon, Su Qingli spent the entire afternoon in the Formation Affairs Room drawing the array path diagram for the sensing array pieces' receiving end. Three pieces of beast skin were spread out on the table in the Formation Affairs Room—each depicting the connection methods for different array nodes. The first was the main receiving array node—connected to the boundary suppression stele. The second was the four sub-array nodes—each connected to one of the four sensing array pieces. The third was the intermediate filtering array node—the one where the Old Formation Master had modified the arc. The array path diagrams on the three pieces of beast skin were connected to each other with extremely fine ink lines—the connecting lines formed a complete sensing array receiving network on the table.

Lu Changyuan stood at the entrance of the Formation Affairs Room. He had just returned from patrolling the Outer Port—the Starlight Coral mother branches in the Outer Port's cold water layer had already spread for nearly fifteen zhang, and the school of Silver-Scaled Moon Fish had increased from twenty to over thirty. The outer fishing team had recruited three new Loose Cultivators yesterday—all of whom had sought them out after hearing about Blue Moon Island's fishing license system.

Su Qingli did not look up. The array brush in her hand moved back and forth over the third piece of beast skin—tracing the curve of the arc three times. Upon the third time, she placed the array brush on the brush rest—then picked up the beast skin and held it against the sunset light outside the window. The sunset light shone through from the back of the beast skin—the ink lines of the array path diagram turned into extremely fine black shadows under the sunset light. The ink at the turn of the arc was the thickest—so thick it was completely opaque.

"This Receiving Formation—" She put down the beast skin. "If all four sensing array pieces are in place—the island protection Formation will know someone is coming when the enemy is still nearly one hundred li away from the island. But there is a problem now."

"What problem?"

"The sensing array pieces capture all spiritual power fluctuations—those of enemies, sea beasts, passing merchant ships, and even large schools of fish. Although the intermediate filtering array node can filter out waves and tides—it cannot filter out merchant ships and schools of fish." She flipped over the last page of the array diagram—the back depicted a row of spiritual power fluctuation waveforms of different frequencies. "I need to set an early warning threshold—fluctuations below the threshold will not trigger an alarm. Where should the threshold be set—too low is equivalent to no filtering, and too high might cause us to miss a real threat."

"The threshold doesn't need to be fixed." Lu Changyuan walked into the Formation Affairs Room—and stood before the table. "Set it to three levels first. Level one—record all fluctuations, but do not sound an alarm. Level two—sound an alarm for spiritual power fluctuations above the Foundation Establishment Stage. Level three—transmit a message directly to me for spiritual power fluctuations above the Golden Core Stage. You can adjust between the three levels at any time—adjust it based on the actual fluctuation data received from the previous month."