Solar Clone picked up one stone and a thin brush. He dipped the brush into the lake clay, then began to paint lines onto the stone's surface, the strokes flowing in a complex pattern.
The first layer he drew was Heatfrost Vyuha: loops and sigils that formed a closed circulation, capable of guiding any essence that entered into either freezing cold or steady heat without losing balance.
As long as power flowed through those lines, the cabinet's temperature would rise or fall in controlled waves, letting the body train between extremes.
Around that backbone, he wove the second layer: Essencewell Vyuha. Here, the lines didn't change temperature; they only gathered and directed.
Thin channels curled around the Heatfrost pattern like roots, their sole purpose to pull ordinary essence from the environment and route it toward the main core that would power all the cabinets.
Once activated, Essencewell would act on its own—slowly absorbing loose essence, storing it inside the core stone, and only restarting its cycle whenever that stored power fell below half.
"These stones are just nodes," he reminded himself softly, flicking his brush to finish a curve.
"You shape the flow, not hold it." When the pattern on the first stone was complete, the lines of clay glimmered faintly as his essence seeped into them, fixing the design so they would transmit power without warping it.
He repeated the process for each cabinet, inscribing the same Heatfrost‑and‑ Essencewell node again and again, until a small pile of finished stones rested on the table beside him.
Finally, Solar Clone carried the stones into the cabinets and fixed them into the inner walls, linking them with thin channels carved through the rock.
Farther back in the cultivation ground, a single, much larger stone waited in its own recess—the true core that held the complete Essencewell Vyuha.
Once he connected the cabinet channels to that core and gave it the first command, the process would become automatic: Essencewell would endlessly charge the core whenever it dropped below half full, the core would feed that stored essence into the node stones, and the Heatfrost lines on those nodes would shape that power into heat and cold the moment a family member spoke the activation word.
With the last connection sealed, he stepped back and nodded in satisfaction.
What had been a rough ground‑scribbled test yesterday had now become a proper formation—an integrated array that drew its own power, regulated its own reserves, and let his family train the Laws of Heat and Cold without anyone needing to stand outside and keep it alive.
He didn't stop with the Heatfrost cabinets. Once the array proved stable, Solar Clone moved through the fortress like a quiet storm, installing Vyuha after Vyuha until the whole underground space began to change.
He set up a separate cabinet for RefreshingBreeze Vyuha, layering his main healing technique with several supporting methods.
Inside that confined space, essence would swirl in gentle spirals, stripping away fatigue, knitting strained muscles, clearing hidden bruises, and even smoothing the agitation from the mind.
A few minutes of rest in there would leave his family feeling as if they had slept deeply for an entire night.
The bigger formations took longer. To spread them through the fortress, he had to carve and prepare countless stones, each one turned into a Vyuha node before being fixed into walls, floors, and ceilings.
Sun‑Moon Vyuha went first: channels and nodes linked to the ceiling, allowing him to pull up a red morning sun, soften it into afternoon light, dim it to silver moon and scattered stars, or sink everything into deep night with a thought. Day and time returned to the cave, even without a real sky.
Next came Essencewell Vyuha, woven through the corridors and chambers. He set several cores at key points and connected them with node stones, so that the fortress itself became a slow‑breathing network of spiritual wells.
The cores quietly drank in loose essence, stored it, and released it in gentle waves, thickening the ambient energy everywhere his family walked or trained.
He dedicated another cabinet to StillheartVyuha. The array etched into that room slowed the breath, steadied the heartbeat, and dampened wild emotional surges.
Anyone who sat inside found it easier to sink into meditation, hold their vows, or review a battle calmly without being pulled back into fear or rage. It became the place they entered before important breakthroughs or after difficult days.
One by one, other formations followed—Impactforge nodes in the training ground, Fieldweave lines in the gardens, Nerveglow circuits near the sparring platforms—until the entire fortress was threaded with subtle power.
By the time the last stone was set and the final channel sealed, Solar Clone felt as if he had rebuilt the cave from the inside out.
Only then did he allow himself to rest, lying flat on the cool floor for a while before sitting up again, mind already turning toward new Vyuhas that could be born from what he had learned.
Ten days slipped past like that. Solar Clone designed, carved, and installed formations from morning to night, occasionally breaking only to train or check the stability of earlier arrays.
Sacral Clone kept to his own steady rhythm: daily watering of the fields, joint training sessions with Solar Clone, and preparing meals rich with Essence Flow and balanced nutrients for everyone.