Chapter 220: Pollution Echo and the Thorn Heart Lock

Their retreat was completely sealed off by wildly surging thorn vines. Those originally serene and peaceful spirit phantoms now had twisted faces, their chanting turned into shrieks full of rejection and malice, their icy gazes locked dead onto Xiang Lingna, who had pressed her arm into the depression on the door! The entire atmosphere of the Thorn Corridor instantly plunged from sacred solemnity into eerie danger!

"Damn it! Knew nothing good would come of this!" Glorna roared, reacting as fast as lightning. Her massive battle axe, carrying a whistling wind, hacked viciously at the wall of thorns blocking the path behind them! Yet those seemingly plant-like vines were unimaginably tough — the axe blade actually sparked off a string of sparks upon striking, leaving only a shallow mark, and instead provoked an even fiercer counterattack from the vines. Countless thorned tendrils whipped toward them like venomous snakes!

Clang-clang-clang! Glorna swung her axe to block, her power armor lashed until sparks flew in all directions. She was forced back a step, shielding Sister Ai Li and Xiang Lingna behind her. "This damned thing is absurdly hard!"

Sister Ai Li endured her injuries and tried to cut the vines with a short blade, but the effect was even more negligible. Zero's console fired energy beams — although they could scorch a small patch temporarily, the vines' growth speed far exceeded the rate of destruction!

And ahead, that massive door of thorns, after Xiang Lingna pressed her arm against it, trembled, emitting a teeth-grinding creak, and was slowly opening inward! But the light leaking through the crack was not pure emerald green — it was mixed with a heart-palpitating, writhing turbid shadow! That faint aura of annihilation-pollution became clearer, even attempting to spread upward along Xiang Lingna's crystalline arm!

Xiang Lingna felt a piercing cold and needle-like searing pain shoot through her right arm. That was not physical damage, but some kind of erosion on the spiritual and energetic level! The door's defense mechanism had indeed been polluted — it no longer distinguished guardians, but attacked any existence that tried to approach!

"Xiang Lingna! Hold on!" Sister Ai Li saw Xiang Lingna's pained expression and the fine black threads beginning to appear on her arm, frantic with worry, yet unable to approach that door. The attacks from the surrounding vines and phantoms grew more and more ferocious!

"Zero! Analyze the pollution source! Find a way to interfere with it!" Glorna shouted while barely withstanding the vines' assault. Although the attack patterns of these vines and phantoms were fierce, they seemed somewhat rigid, as if executing some fixed program.

Zero's console, dodging with difficulty amidst the dense attacks, focused its scanning beam on that opening door. "Pollution source locked: core within the door body, deeply entangled with guardian energy… conventional means cannot separate… attempting reverse analysis of guardian protocol… searching for priority override command…"

Just as Zero calculated at full capacity, Xiang Lingna, in her extreme agony, felt her consciousness seemingly forge a deeper connection with that ancient energy on the door. Within those sharp, rejecting noises, there seemed to be some fragmented shards of thought filled with sorrow and despair — the final cries of those spirits who had left their imprints!

【…Stop it…cannot let it pollute the 'Heart Lock'…】【…The legacy must remain pure…otherwise it will be a new disaster…】【…With blood, with soul…reinforce the seal…】【…Later comer…be careful…the shadow…within the light…】

Heart Lock? Legacy? The shadow within the light?

Xiang Lingna suddenly looked up, toward the area around that palm-shaped depression on the door, at those inscribed ancient spirit characters and World Tree emblems. Under the mixed light's reflection, she suddenly noticed that certain lines of those emblems seemed…to form another, more hidden pattern resembling thorns entwining a sharp sword! This pattern gave her an inexplicable sense of familiarity…resonating faintly with those most primordial Thorn Order imprints bestowed by Priestess Liyana, deep within her right arm's crystal!

Could it be…that the true authority is not simply World Tree energy, but some specific imprint containing the will of the Thorn Order?

This thought flashed through her mind like lightning! She immediately tried, no longer merely activating the emerald energy from the World Tree sapling within her right arm's crystal, but concentrating her entire will to communicate, to summon that unique Will Brand belonging to Priestess Liyana, representing the Moon Goddess Priestess and Thorn Guardian, hidden deepest within the crystal!

This process was extraordinarily difficult. Her spiritual power was nearly drained, her head splitting with pain, and the searing agony in her right arm surged against her consciousness like tides. But she gritted her teeth and persevered, constantly recalling in her mind Sister Liyana's gentle yet resolute face, recalling the scene of her manipulating thorns to purify pollution!

Gradually, the light emanating from her right arm's crystal changed! No longer pure emerald, but clear, sharp thorn patterns like silver blade-edges emerged! These silver thorn patterns interwove with the emerald light, radiating an entirely different, sharper, more resilient fluctuation of order, filled with the resolve to guard and purify!

When this light, mixed with silver thorn patterns, touched that depression on the door—

Hum!!!

The entire door of thorns trembled violently! That hidden thorn-sword pattern on the door suddenly blazed with brilliant silver light, like an awakening dragon!

Those turbid shadows mixed within the light, as if encountering their bane, let out sharp, terror-filled shrieks and rapidly contracted and retreated back into the door like a tide! The black threads spreading toward Xiang Lingna's arm also instantly snapped and dissipated!

At the same time, the wildly attacking vines and malicious spirit phantoms around them suddenly faltered! Their twisted expressions softened somewhat, and a trace of residual, ancient-spirit bewilderment seemed to return to their hollow eyes. Their attacks became sluggish and chaotic. The shrieking noise also once again intermingled with some intermittent fragments of the original solemn chanting.

It works! The Thorn Order is one of the true highest authorities here!

"Nicely done, girl!" Glorna's pressure greatly reduced, and she seized the chance to chop apart a large swath of hesitant vines with one swing of her axe.

Zero also caught this change: "Detected guardian protocol priority change! Pollution temporarily suppressed! Door opening in pure mode!"

Creak—boom!

The heavy door of thorns finally swung fully open, revealing the scene behind it.

Behind the door was not some treasure-filled storeroom, but a small, circular altar-like chamber. In the center of the chamber was a platform likewise entwined with thorns. The platform was empty, bearing only a clear imprint where some kind of box had once rested — exactly the shape of that treasure box into which the priestess had placed the World Tree seed in the earlier image. But now, the treasure box was gone.

And directly above the platform floated a soft, constantly shifting milky-white orb of light, within which countless tiny spirit characters seemed to flow — a highly condensed information carrier.

Apart from this, the chamber was utterly empty. The so-called "legacy" seemed to consist of nothing but this orb of information.

However, in the corner of the chamber, a small puddle of dried, blackened, asphalt-like stain remained on the ground, emanating a faint aura of annihilation. Clearly, pollution had once penetrated here, and…someone, or something, had taken that treasure box containing the World Tree seed one step ahead!

The group carefully entered the chamber. The door of thorns behind them did not close, and the vines and phantoms outside also ceased their attacks, becoming quiet once more — only the phantoms' gazes remained hollow, as if they had lost their target.

Xiang Lingna collapsed to the ground in utter exhaustion. The pain in her right arm had lessened slightly, but her spiritual consumption was enormous.

Zero's console approached that milky-white orb of information and began attempting to read it.

A massive stream of information poured into Zero's database like a tide — mostly fragmented logs, star charts, technical snippets. In the end, a relatively complete message, carrying that priestess phantom's final thought, was played back by Zero:

【"…Latercomer, if you can hear this message, it means the 'Thorn Heart Lock' has acknowledged you, and it also means 'New Oasis' has reached its most perilous moment…"】【"…The 'Dawn Seed' in the treasure box has been stolen by 'Shadow Pupil'…he betrayed us, threw himself into darkness, believing only the power of annihilation could allow the spirits to 'evolve'…"】【"…He took the seed and fled toward the Ark's deepest 'Shadow Engine', attempting to use the chaotic energy and rifts there to pollute the seed and forge a key to darkness…"】【"…Stop him! Absolutely cannot let him succeed! Otherwise, the Ark's remaining hope will be completely extinguished, and this star domain will face true doomsday…"】【"…The entrance to the 'Shadow Engine' is at the energy well's…very bottom…that place has been completely devoured by darkness…extreme…caution…"】

The message cut off abruptly here.

Shadow Pupil? A betraying ancient spirit? Shadow Engine? The pollution in the lower-level rifts indeed has a source! And the final World Tree seed has actually fallen into the traitor's hands and is being polluted!

The sliver of hope just glimpsed was instantly shrouded once more by an even greater gloom.

And just then, Zero suddenly emitted an urgent alarm!

"Detected high-intensity energy fluctuation surging into the energy well cavity from outside! Source: Doctor's main fleet! They are firing some kind of…non-destructive energy containment device toward the energy well entrance! Attempting to seal and stabilize the entrance!"

"Simultaneously detected multiple high-energy signatures entering rapidly through the stabilized entrance! Energy signature identification: Scavenger improved model…and…unknown high-tier units!"

The Doctor indeed has not given up! He is even seizing the moment when the leyline energy revives and stabilizes, attempting to forcibly occupy this place!

The traitor and the polluted seed crisis ahead, the Doctor's army pressing from behind!

They were completely trapped in this newly discovered altar chamber!