Global Survival: I Got the D-Rank Personnel Simulator-Chapter 70: Level 70.2 Shelter

Entering the red room, Lin Ye found only a single red metal treasure chest inside.
The chest disappeared upon opening, revealing two items: a shelter upgrade blueprint and a low-tier spatial crystal.
[Use 2nd-tier shelter upgrade blueprint?]
"Use."
[Collect 10 mutation organs from 1st-tier Mutation Creatures as shelter upgrade materials (0/10)]
'Already obtained one? Do deeper maze levels have higher blueprint drop rates? Or is it time-related?'
Lin Ye was surprised. Blueprint drop rates during system events had always been low, yet he'd gotten one from the first chest this time.
'There are still organ reserves in the shelter's freezer. I can upgrade immediately after returning.'
Storing the spatial crystal, Lin Ye continued exploring the maze. Like on the first floor, he quickly navigated through corridors searching for locked rooms.
Soon he found a second locked room, but didn't approach the door - most of that corridor was submerged in some kind of red liquid, with the locked door sitting within it.
'...Better take another path.'
Lin Ye didn't hesitate long before abandoning this room. Recent experiences had taught him never to touch unknown liquids.
Taking a different corridor, Lin Ye soon found another locked room. Using his key to open it, a 1st-tier blood-corpse charged out.
Drawing his blade, Lin Ye dealt with the creature. Just as he was about to enter the room, faint tapping sounds came from the corridor's end.
Click-click-click-click...
A blood-corpse with six sharp limbs rounded the corner, entering Lin Ye's field of vision.
The abomination resembled a hairless spider mutated from a human - its torso remained humanoid, but where legs should have been had melted into a dark red tail.
This monstrosity served as another reminder of mutation's dangers. Without proper control, this would be the fate of all spiritual energy absorbers.
The human-spider charged at Lin Ye, its six limbs tapping rhythmically against the floor.
Lin Ye scanned it with his mental energy:
2nd-tier Mutation Creature. Three mutation organs: an energy-controlling organ in its abdomen, its foremost limbs, and the tail.
Without speed runes, the creature moved much faster than Lin Ye, so he stood still, intently sensing its movements.
The human-spider rammed into Lin Ye while thrusting its front limbs at his head and torso.
Activating the mutated spiritual energy shield from his Nightfall Formalwear, Lin Ye blocked the attacks while driving Red Blade into the creature's abdomen, shredding its internal organ.
Thud!
The tail smashed against the energy shield, shattering it and sending Lin Ye flying back slightly.
Lin Ye used the momentum to retreat further. With its organs destroyed, even a Mutation Creature couldn't ignore such damage - buying time would make it easier to handle.
The human-spider kept charging as if unharmed, but Lin Ye sensed its unstable condition. Activating the acceleration rune inscribed on his pants, he rapidly retreated.
Once the creature weakened, Lin Ye counterattacked, using a Severing rune to slice off its front limbs.
When the tail whipped toward him again, Lin Ye hastily created another spiritual energy shield to barely block the strike before using Red Blade to remove its last mutation organ.
After dealing with the human-spider, Lin Ye processed its corpse while absorbing ambient spiritual energy.
The red maze wasn't a battlefield - its energy density couldn't sustain continuous rune activation, forcing Lin Ye to consume his internal reserves when chaining runes. Additionally, spiritual energy items required cooldown periods between uses.
From the corpse, Lin Ye retrieved an unfamiliar red card different from Mutation Cards, which he'd have to examine back at the shelter.
Collecting three 2nd-tier mutation organs and some usable spiritual materials, Lin Ye left the mutilated corpse behind.
The previously opened red room contained another metal chest holding a bundle of red fabric.
'Some kind of spiritual material?'
Storing the fabric, Lin Ye continued exploring.
Encountering several more liquid-flooded corridors, Lin Ye cautiously avoided these anomalous zones.
The detours cost significant time before finding a third locked room.
Inside waited another 1st-tier blood-corpse. This time, instead of killing it immediately, Lin Ye amputated its limbs, continuously severing newly mutated appendages until it was sufficiently harmless.
The room's metal chest contained only a sealed metal syringe.
Pocketing the syringe, Lin Ye grabbed the blood-corpse by the neck like a rabbit and carried it back to the red liquid corridor.
From a safe distance, he hurled the disabled creature into the liquid.
Upon contact, the blood-corpse rapidly mutated - within ten seconds, it transformed from a limbless wreck into a miniature human-spider covered in appendages.
Its piercing shriek echoed as dozens of tiny legs scrambled toward Lin Ye.
Lin Ye turned and ran - not from fear of the creature, but to avoid the liquid. That terrifying mutation speed meant even slight contact would cause localized bodily mutations.
He wasn't keen on growing strange appendages.
Only after establishing spiritual energy barriers ensuring no liquid contact did Lin Ye stop to swiftly dispatch the miniature abomination.
This time he didn't bother dissecting it. While intrigued by the mutation-accelerating liquid, he currently lacked the means to safely study such dangerous substances.
The maze's deep level contained numerous flooded areas that severely hampered exploration. When the countdown ended, Lin Ye still hadn't found the special deep-level room.
....................
Returning to the shelter where Brother Chicken still incubated its egg, Lin Ye immediately submitted ten frozen mutation organs for the upgrade quest.
[Shelter upgrade quest completed. Upgrade shelter tier?]
"Yes."
[Upgrade complete]
Lin Ye checked the updated shelter information:
[Shelter Information]
[Tier: 2]
[New Function: Basic Loot Space]
[Status: Absolutely Secure (21 days, 13 remaining)]
[Note: Upgrade your shelter tier within 21 days]
The Basic Loot Space function resembled the previous loot space but only provided one cubic meter of storage, requiring manual item placement. This function only worked during system events, not simulation missions.
With the upgrade complete, Lin Ye began examining his new acquisitions.