As the heavy stone door slowly opened amid a rumbling sound, a dim, cold aura rushed at his face.
Lin Mu once again stepped into the Gu Storage Cave.
But it was utterly different from every previous occasion.
This time, the two elite guards standing at the entrance did not inspect his token; instead, with expressions of the utmost respect, they called out loudly: "Greetings, Clan Elder Lin Mu."
Lin Mu nodded slightly and strode inside.
Passing through the outer region, he did not even linger before the stone racks of Rank 1 Gu worms; instead he headed straight for the deepest part — that region of Rank 3 Gu worms protected by layer upon layer of formations.
With a different realm came a naturally different field of vision.
Those low rank Gu worms he had once needed to scheme over with careful calculation had now, in his eyes, mostly fallen behind the pace of his Rank 3 middle stage.
Standing before the Rank 3 stone racks that radiated a variety of auras, Lin Mu was in no hurry to make his selection; rather, he closed his eyes, sank his mind into his aperture, and took stock of his current foundation.
He understood very well that with Gu worms, more had never meant better.
What a mature and lethal combat system required was not a disorderly pile of Gu worms, but several genuine top grade items that could revolve around a core, coordinate with one another, and produce chemical reactions.
At present, the Gu worms in his aperture that truly served for main combat were:
Rank 3 Metal Sever Leaf Gu — this was his Vital Gu now, and also his absolute core means of attack.
Rank 3 Steel Shield Gu — that passive defensive Gu bought at great expense, the final insurance for preserving his life at moments of crisis.
Rank 2 Jade Tendon Gu — a top grade tool for hardening the flesh and reflecting damage.
Rank 2 Stick Insect Gu — not only usable as a heavy close combat weapon, but also an excellent trump card for ambush and blocking.
Rank 2 Earth Spike Gu — a once useful means of ground based lethality.
Rank 2 Leaping Rabbit Gu — the movement core that supported his bursts of evasion.
Rank 2 Red Mud Gu — this hard laboring, greatly meritorious Gu worm had not only participated in constructing his self created killer move "Earth Ring Body," but further bore the excellent auxiliary role of concealing traces and altering terrain.
As for the rest — the Dust Cleansing Gu, Four Flavors Liquor Worm, Dust Escape Gu, Crystal Corrosion Gu, along with some basic healing and reconnaissance Gu — all belonged to functional auxiliary slots.
"Now that I have stepped into Rank 3, the large number of Rank 2 Gu worms remaining in this system have grown more and more inefficient."
Lin Mu opened his eyes, feeling no small measure of sentiment.
Before entering the Gu Storage Cave, he had already sold off the Earth Spike Gu, the Leaping Rabbit Gu, and several other low rank Gu worms that had long been gathering dust or whose functions had begun to overlap, exchanging them for military merits.
"As for that combination killer move, Earth Ring Body…"
Lin Mu deliberated inwardly.
"With the Leaping Rabbit Gu phased out, this tactic can only be shelved for the time being. Once I have a more complete, higher rank system later on, I can simply reconstruct it."
That said, not all low rank Gu would be phased out.
Lin Mu still retained several Gu worms whose strategic value remained irreplaceable.
The Red Mud Gu stayed.
Not because it could still serve as a core combat Gu, but because as a "tool Gu," its value could not be measured by rank.
The Jade Tendon Gu stayed. It had long since perfectly integrated into Lin Mu's close combat system, becoming an inseverable part of his physical foundation.
The Dust Cleansing Gu stayed. It would continue to nurture his flesh imperceptibly.
The Four Flavors Liquor Worm stayed. Though at present it could no longer purify Rank 3 Silver Primeval Essence, there remained the possibility of refining it higher in the future; such a heaven defying top grade item absolutely could not be sold off for a bit of military merit in the here and now.
The Dust Escape Gu stayed.
Though it was only Rank 1 and had utterly fallen behind in main engagements, its function of obscuring vision was exceedingly special — he could simply toss it into the depths of his aperture to gather dust.
If he encountered certain special environments in the future, it might yet produce an unexpected effect.
Lastly, that Stick Insect Gu, which had transformed into a strand of hair hidden behind his head, stayed as well.
It differed from ordinary attack Gu; with its rigid main body, its unexpected concealment, and its long accumulated combat familiarity with Lin Mu, it could exist perfectly well as a close quarters murder weapon and an unforeseen trump card.
After such a clearing out, what remained were all the sharpest, most streamlined blades, most suited to his way of survival.
Having finished the cleanup, Lin Mu walked before the clan elder in charge of registration.
Once all his military merits had been tallied in full, the corner of Lin Mu's mouth curved up slightly. Not bad — it had finally reached what he required.
Standing here today, he in fact possessed a full three sets of absolute authority to select Rank 3 Gu worms!
The first was his formal benefit for being promoted to clan elder.
This was the starting resource that Black Blood Stockade normally granted to newly elevated upper echelons.
The second came from that tacit, unspoken secret transaction he had conducted with Lin Cang in the side chamber that day!
The resources he had traded for were not only enough to refine his Vital Gu ahead of schedule into the Rank 3 Metal Sever Leaf Gu.
As a bonus, Lin Cang had further swept his hand and additionally promised him one instance of authority to select a Rank 3 Gu worm!
As for the third, it was a merit exchange quota he had scraped together using his prior accumulation of military merits plus the conversion value of that batch of phased out Rank 2 Gu worms.
Three.
A full three rights of selection for Rank 3 Gu worms!
Counting further the newly refined, keen edged Metal Sever Leaf Gu, the ever reliable Steel Shield Gu, and that Crystal Corrosion Gu which had aided his breakthrough, it was in this very moment that Lin Mu truly experienced the thrill of "trading a shotgun for a cannon."
He wasted no time and strode directly toward the first row of stone racks.
The first: a combat Gu.
Lin Mu's objective was exceedingly clear.
He had no need to select any attack Gu of tremendous power, for the Metal Sever Leaf Gu's ability to break through anything was already sufficient to shoulder the burden of core lethality.
What he lacked most now was a means to ensure the enemy could not easily evade the Metal Sever Leaf!
His gaze swept swiftly across the array of Rank 3 Gu worms, and very soon locked onto a Gu worm that was black all over, shaped like a single link of an iron ring.
Rank 3 — the Iron Chain Gu!
This Gu worm was not responsible for primary lethality; its use was exceedingly singular yet exceedingly loathsome: once mobilized, it could condense chains of Primeval Essence, tough beyond compare, to wrap and drag at an enemy with utterly shameless persistence, forcibly locking down the opponent's limbs and wrecking their movement techniques and balance.
Looking at it, Lin Mu had already conjured in his mind the lethal combination to pair with it: first restrain with the iron chains, then kill in one blow with the Metal Sever Leaf!
A killing setup that in his Rank 1 and Rank 2 days had required half a day of groundwork with other Gu worms to accomplish might now, with this Rank 3 control Gu, require only the briefest instant.
"The first: confirmed."
Lin Mu took it into his possession and walked naturally toward the region of defensive Gu worms.
The second: a defensive Gu.
Though he currently had the Steel Shield Gu, that Gu worm was passively triggered — the final insurance under a lethal crisis; and the Jade Tendon Gu leaned too heavily toward physical close combat and damage reflection.
What he truly lacked was a Rank 3 defensive means that could be actively activated, for coping with conventional high intensity firepower saturation.
After ruling out several Gu worms that offered all around protection but consumed enormous amounts of Primeval Essence, Lin Mu's gaze halted upon a Gu worm resembling a black shield.
Rank 3 — the Iron Curtain Gu!
This Gu worm's characteristics were exceedingly distinct.
Once mobilized, it would form a high intensity black defense at a location designated by the Gu Master.
Its shortcoming was that it could not truly achieve complete body protection in every direction, but its strengths were equally prominent — its frontal defensive power was exceedingly formidable, and its Primeval Essence consumption relatively low.
This did not conflict in the slightest with Lin Mu's own system; it could be counted as plug and play.
The Iron Curtain Gu handled hard blocking at the outer layer, the Jade Tendon Gu handled damage reduction in close quarters melee, and the Steel Shield Gu handled preserving his life.
Three lines of defense, clearly stratified, solid as an iron cauldron.
"The second: confirmed."
Two Gu worms had been selected with exceeding smoothness.
However, when Lin Mu made his way to the region housing Rank 3 movement type Gu worms, his footsteps came to a halt.
Facing those several movement Gu on the stone racks, each radiating its own aura, he began to hesitate.
His reasons were also entirely sufficient.
How to choose an attack Gu — one need only look at lethality and control; relatively simple.
How to choose a defensive Gu — one need only look at systemic complementarity; not difficult either.
But a movement Gu was utterly different.
It directly determined what manner of combat style Lin Mu would adopt hereafter, and even determined in what posture he would survive upon that vaster, crisis ridden land of the Southern Border.
Upon the stone racks before him were placed the pinnacles of several different schools.
There were Gu worms that pursued purely instantaneous bursts, exceedingly fast, like teleportation, but which drank Rank 3 Primeval Essence the way a great whale drinks water;
there were Gu worms adept at long distance charges, slightly inferior in absolute speed yet winning out in endurance, an excellent tool for travel and flight through the mountain forests of the Southern Border;
there were Gu worms adept at darting and weaving within a small radius, not fast in absolute speed, but with exceedingly bizarre evasive movement, most suited to entangled fighting across complex terrain.
There was even, within a jade box at the very top, a Gu of exceeding preciousness that could allow a Rank 3 Gu Master to achieve "brief airborne gliding."
Every single option carried exceedingly obvious strengths and weaknesses.
Lin Mu stood there, brows tightly knit.
He understood clearly by now that this tiny Black Blood Stockade would absolutely not be his final destination.
That being so, what he chose this time was by no means merely a matter of considering the next battle.
Rather, it was a matter of considering how he would walk when he truly set foot upon the Southern Border.
He picked up several Gu worms in turn, examined them carefully for a long while, then slowly set them back down.
Time trickled away drop by drop.
Even that clan elder who had all along been standing not far off, responsible for guarding the cave, could not help glancing at him several times before speaking up to ask:
"Clan Elder Lin Mu, have you still not decided?"
Lin Mu did not answer.
He merely gazed quietly at these several Gu worms before him.
For a long while.
He drew a deep breath, and that trace of hesitation in the depths of his eyes was utterly eliminated.
His gaze at last halted, unwavering, upon one of the Gu worms, and he reached out to grip it tightly in his palm.
"This one, then."