Sanatorium

Biodata

Feature	Value
Name	Angel Psychiatric Sanatorium 4
Alias(es)	Sanatorium; Angel Asylum 8 41
Type	Psychiatric institution reproduced as a horror-game instance within Xu Han’s corrupted dream 41 43 48
Affiliation	Stairway to Heaven survival game 3 4
Occupation/Role	Escape instance; site of the director’s human-sacrifice ritual 4 29 47
Administrator	The director, who controls the corrupted dream domain 43 44
Layout	Nine floors, mezzanines, and a basement parking garage 4 5
Status	Active during its second opening; still in testing, with its danger level initially undetermined 4
First Appearance	Yu Qing enters the instance 4

Power Progression

Stage / Realm / Level	Chapter	Notes
Instance Level 1	4	Initial classification on Yu Qing’s arrival. The system questions whether it is suitable for newcomers and explicitly disclaims responsibility for deaths.
Instance Level 3	17	Discovering the “Secret of the Angel Statue” intensifies the angel’s murderous intent. The nurse transforms into a skeleton in broad daylight.
Instance Level 5	39	Further changes in Xu Han raise his brutality to unprecedented levels. The instance crosses the danger threshold at which NPCs can break established rules to kill players.

• Boss level is separate from instance difficulty: viewers recall a level-four boss during the previous opening, while Yu Qing encounters a level-seven Black Fog entity during the second run 5 8.

Instance Conditions

Condition	Details
Main objective	“Find the key to escape and embrace your new life” 4.
Time limit	Seven days 4.
Clearance reward	20,000 points 4.
Exit barriers	An inner wooden door opened by an access card and an outer iron door requiring a separate key 40.
Story exploration	A side objective distinct from escape. Yu Qing reaches 99% without finding the key 47 48.
Top-floor mission	Explore the ninth floor within one hour; failure automatically reduces the assigned streamer’s HP to zero 24.
Boss-exclusive game	The BOSS chooses the rules but may initiate this game only once per day 19 22 24.

Background / History

The Director’s Takeover

The director acquired the sanatorium after using a manufactured, youthful appearance to deceive its female owner. Under the pretense of marriage, he murdered her and took her position. He then placed his dead mother inside the Angel Statue in the lobby 48.

His pursuit of replacement skin extended to the sanatorium’s patients. His diary describes them as disposable and records the use of living sacrifices to suppress his mother. Xu Han discovered the ritual and condemned it; the director murdered him, hollowed out his organs, filled his body with mercury, and made him the ceremony’s permanently smiling priest. An impostor subsequently assumed Xu Han’s identity and abused his wife and daughter 21 47.

Xu Han’s Dream

Xu Han’s family had lived in the sanatorium’s staff dormitories. His daughter, Xu Tang, recorded family memories there, including her wish that her father could someday buy the entire institution 26.

After his stomach-cancer diagnosis, the director wrote that selling his soul to the Deity could grant his wish to remain with his mother in a place with a sanatorium. Yu Qing later infers that the Deity fulfilled this wish by corrupting Xu Han’s dream, allowing the director to remain there and turning the dream into a Dungeon for challengers 47 48.

The dream’s imagery draws on Xu Han’s memories and fears. His description of his dieting wife as a “bag of bones” corresponds to the nurse’s skeletal form; a frightening story told to Xu Tang manifests as the hopping Sprinkler Granny. The punishment of anyone who speaks becomes bloodied whips protruding from the walls 41.

Previous Opening

During the second opening, viewers recall that nearly eighty people entered the previous run and none escaped. They also recognize creatures such as Rabbit Girl, whose earlier behavior made players avoid her 8 20.

Layout and Appearance

• At night: peeling walls, bloodstained floors, flickering yellow lights, and black mist make the building hostile and difficult to navigate 4 38.
• By daylight: bloodstains disappear, walls become smooth and white, and flowers and greenery make the institution resemble an ordinary sanatorium 14.
• Unreliable floor numbering: the elevator has only six buttons despite the nine-floor plan and basement. Mezzanines are essential to interpreting directions such as “lower third floor” 5.

Area	Location	Features and significance
Lobby and reception	First floor	Admission registration, bell distribution, room-key collection, the Angel Statue, and the locked exit 14 15 17 40.
Psychiatry department	Second floor	The doctor records patients’ names and selects a nightly morgue guard. He states that psychiatry is the sanatorium’s only medical department 14 15.
Cafeteria	Lower third floor / third-floor mezzanine	The destination identified during the Black Fog warning. It is also the site of the sacrifices’ forced feeding 5 29 31.
Director’s Office	Seventh floor	Contains access cards, a photograph of the director and his mother, the Director’s Diary, and a mirror hidden behind a wall 31 46 47 48.
Morgue	Ninth floor	Yu Qing’s starting point; contains Xu Han’s corpse and receives patients assigned to guard duty 4 15.
Small patient rooms	Ninth floor	More than fifty closely packed rooms containing diaries that document the sacrifices’ conditioning 25 27 29.
Patient wards	Includes ward 104	Rooms accommodate two patients each. Yu Qing and Qian Lai share ward 104 15 16 17.
Detention Room	Unspecified	Punishment area for disobedient patients and a location where Yu Qing encounters the BOSS 27 32.
Parking garage	Basement level one	Yu Qing uses it to establish the correct route to the lower third floor 5.
Backyard and Wishing Pool	Behind the wards	Contains another angel statue and the circling, water-spitting Sprinkler Granny 25.

Rules and Hazards

Bells and Identity

• Protective bells: the nurse says ghosts will not kill people wearing the director’s blessed bells. Both patients and staff—including the director—wear them 14 16.
• A bell must ring: a silent bell leaves its wearer vulnerable to ghosts at night. Yu Qing disables the doctor’s protection by removing and hiding its clapper 16.
• Clothing and badges determine identity: the sanatorium recognizes people through their garments and name badges. Wearing Xu Han’s coat and badge allows Yu Qing to assume the doctor’s authority and later fool the director into treating him as staff 22 23 27.

Patient Restrictions

• Do not attack doctors: patients are told that only doctors may harm patients. Hu Zibiao’s hand decays when he grabs the doctor’s collar 14.
• Keep quiet: loud noises provoke bloodied vines that lash out from the walls. Silencing Qian Lai allows him and Yu Qing to retreat from an attack 17.
• Nightly morgue duty: one patient is selected by roll call to guard the morgue. Players attempt to evade selection by registering cumbersome or unreadable names 15.
• Remain in the wards at night: the director threatens patients found outside with detention and sacrifice to Angel 27.
• Room assignments: patients must collect their room key cards and follow their assigned two-person accommodation 15.

Limits of Protection

• Black Fog drains health: inhaling it accelerates HP loss. Holding one’s breath slows the damage but does not stop the entity from pursuing or physically restraining a player 5.
• The designated safe area is not absolute: the Black Fog follows Yu Qing into the lower-third-floor cafeteria and seizes him there 5.
• Daylight safety is conditional: the morning broadcast declares the danger over, but discovering the statue’s secret brings a skeletal transformation into daytime 14 17.
• Level-five rules are unreliable: after the difficulty increase, NPCs may break the old restrictions to kill players 39.
• The system can correct deviations: after Yu Qing disrupts the scenario, NPC activity freezes for ten minutes while the system repairs the instance. The director resumes activity immediately afterward and intercepts the escape attempt 32.

Sacrificial Ritual

Phase	Treatment of victims
Forced feeding	Selected patients are made to eat human flesh in the cafeteria while Granny terrifies them with darkness, noises, and accusations from supposed victims 29.
Repeated psychological abuse	The feeding and terror continue for a month, repeatedly leaving victims unconscious or severely distressed 29.
Ninth-floor conditioning	Victims undergo electric shocks and brainwashing while being required to thank and worship the director as their savior 29.
Recorded transformation	Compulsory diaries let the director monitor the victims’ changing beliefs, from identifying as human to identifying as zodiac animals 29.
Skinning and implantation	“Qualified” victims are skinned, fitted with animal fur, and arranged around the Angel Statue 29.
Rejected sacrifices	Those deemed unsuitable retain their skin but are sent to the morgue and tied to beds. Their subsequent purpose is not established by the patients’ diaries 29.

• Victims: the documented animal sacrifices are women and girls. Small children are selected for roles such as the rabbit, which is assigned to Xu Tang 29.
• Enforced silence: victims are forbidden to scream or call for help throughout the process; the doctor punishes noise with a whip or belt 29.
• Purpose: the Director’s Diary identifies the living sacrifices as a means of suppressing his mother inside the statue 47.
• Priest: Xu Han retains human form because he is made to preside over the ceremony rather than serve as an animal offering 41 47.

Notable Inhabitants

• The Director — Controls the corrupted dream and the institution’s sacrificial operation. His arrival can halt supernatural destruction and restore damaged corridors 27 44.
• The BOSS / Black Fog entity — A level-seven being with a humanoid core, a layer of black tentacles, and an outer shroud of mist. It can manipulate temperature and interrupt the system connection; other NPCs fear its authority 33 39.
• Xu Han — Murdered staff member, ritual priest, and original dreamer. His daughter’s grief awakens him, but the Dream Core reveals that he has not controlled the dream for a long time 26 27 43 47.
• The impostor doctor — Assumes Xu Han’s identity and commands female ghosts through violence and their conditioned fear of his belt. Yu Qing strips him of his authority and leaves him to the ghosts’ revenge 21 22 23.
• The receptionist nurse — Xu Han’s wife and Xu Tang’s mother. She distributes protective bells, transforms into a skeleton, and suffers abuse from the impostor and director 14 21 31.
• Xu Tang / Tangtang / Rabbit Girl — Xu Han’s daughter, lured by the director with candy and conditioned into the zodiac rabbit 20 26 29.
• The director’s mother — The flayed woman sealed inside the Angel Statue. Her account reveals how her son acquired the sanatorium; her ghost fades in dawn sunlight 46 48.
• Cafeteria Granny — Torments sacrifices during meals. After Yu Qing kills Granny Ghost, an empty red dress and wig continue serving food in her voice 9 29 31.
• Female patient ghosts — Victims controlled by the doctor’s abuse who later cooperate with Yu Qing, take revenge on the doctor, and help investigate the dream 22 23 41.
• Skeleton orderlies — Enforce detention and collect sacrifices. Their small brains are concealed near the tops of their skulls 20 21 32.

Escape Investigation

Access Cards

• Yu Qing takes the director’s access card, then discovers and removes an entire box of cards from his office 31.
• One card is accepted just as the system’s correction period ends. Before the group can leave, the director captures them 32.
• Later inspection establishes that the card opens only the inner wooden door; the outer iron door still needs a key 40.

The Dream Core

• Yu Qing identifies the sanatorium as Xu Han’s dream through its memory-derived monsters and the dark-purple abyss visible beyond damaged walls 41.
• Qian Lai proposes breaking through the building’s boundary to reach the Dream Core, where they expect to find the escape key 41.
• The Core is already corrupted, its key is missing, and Xu Han has long since lost control of it 43.
• Yu Qing marks the sanatorium’s outer wall with his blood before leaving, enabling him to locate the route back through the darkness. Their explosive reentry accidentally injures the director 44.

Final Search

• Exposing the director’s control of the dream raises story exploration to 78%. Identifying his mother inside the statue raises it to 91%, and finding his diary raises it to 99% 44 46 47.
• The mirror concealed in the Director’s Office does not provide the anticipated confrontation with the director; the BOSS instead traps Yu Qing there 48 49.
• With two hours remaining, Yu Qing destroys the pillar beneath the Angel Statue and finds the director hiding inside its coffin. A search of the director produces no key 50.
• Yu Qing then appears to realize where the key is and stages a surrender to lure out the BOSS. The key’s location and the result of this plan are not revealed in the provided chapters 50.