No, I'm not a human.

A bald guy with glasses. To check, pay attention to his hands, armpits, and the photo. If it's a person, there will be a bandage on his hand with no signs of inflammation, his armpits are clean and hairy, and in the photo, his silhouette is colored in three distinct colors—red, green, and yellow. If it's a guest, there will be noticeable redness around the bandage, fungus is visible in the armpits, and a blurred whitish outline will appear next to the yellow silhouette in the photo.
Punk girl. If the Guest is bleeding gums.
Enerzhek. The teeth, hands, eyes, and armpits are examined. If it's a person, the mouth will have a green tint with yellow teeth, the hands will be clean, the eyes will be green, and the armpits will be neat and hairy. If it's a guest, the mouth will be completely green, the nails will be dirty, the eyes will be noticeably red, and the armpits will appear dirty.
A girl with tattoos. The main clues are her hands and the photograph. All her nails are intact, and the background in the photo is divided into black and white halves. The guest is missing one nail, and a white circle appears in the photo, with someone else's hands visible around the silhouette.
Tourist. If a Guest, the eyes are red. On the 3rd or 4th day of interaction, they may give out a random item.
A guy in a striped jacket. The man's teeth and gums are clean, but there are wounds on his knuckles. The guest has blood on his gums, and a rash has appeared on his hands instead of wounds.
Fraer. If it's a Guest, there's a rash on my hands, my eyes are red, and my pupils are constantly darting around.
Guitarist. Testing criteria have not yet been determined.
A graduate. If the guest has dirty hands and a black aura around their silhouette in the photo.
Mortgage. If the Guest is a fungus on the armpits.
Leper. If you're a Guest, white spots appear on the photo, your teeth are white, and your armpits are shaved.
A guy from a mental hospital. If he's a Guest, he has cavities.

A boy in a raincoat. His lines make no clear sense; he constantly claims he's in the wrong house and then wanders off in an unknown direction. He's not connected to the other characters in any way, and he can't be allowed into the house or checked for signs of the Guest.
A bald man. He visits the player repeatedly, leaving strange instructions. His condition worsens over time. First, he asks to let in a woman with a cat, then not to check on anyone for two days, then to dig a hole in the basement and jump into it at a certain point. If his instructions are ignored, he will stop appearing.
Mushroom Picker. Under certain conditions, he appears on Cashier's Day and tells the player about a mushroom ritual that must be stopped. He will give the player pages of the "Manual of Smiles." If all instructions are followed, he will return and offer to accompany him to Mushroom Country to stop the mycelium growth. He is extremely friendly.
Courier: appears at night, but only if an order was placed during the day at the ForRest supermarket, and brings the selected item.

A maniac. From the very beginning, he asks to be taught how to kill. If he's a Guest, he'll have red eyes with green irises, yellow teeth with bleeding gums, and black nails.
Shot. Victim of the Guest Hunter. If a Guest, the armpits are scratched and irritated.
Gangster. A charismatic and aggressive tenant who immediately tries to establish dominance. If a Guest—bleeding gums and armpit fungus.
Twins. One of them is depressed. Both sisters can be Guests either simultaneously or separately.
The Gravedigger. He has very subtle characteristics. The only noticeable difference is that in his Guest photo, he'll have a few shadows around him.
The Landlord. He's always dissatisfied with what's going on and constantly cites laws, such as demanding a gun license. If he's a Guest, he'll have shaved armpits.
A positive man. Experience has taught him that anger destroys everything around him, and that the most important thing in this world is humanity. If the Guest is there, he'll get a rash on his hands.
The wife of a member of the Emergency Situations Committee. She once reported a neighbor to the Emergency Situations Committee, after which her husband was taken away. Despite her outward sense of pride, she's actually upset that she wasn't hired instead. If she's a Guest, her nails are painted and her eyes are red.
Discord moderator. Listed on his phone as "Aggressive Guy." If a Guest, he has white teeth, bite marks on his hands with broken nails, and shaved, irritated armpits.
Dream Stealer. Claims to be able to see other people's dreams, causing him to sleep poorly. During conversation, he shares a strange dream he had with the protagonist. If the Guest is present, he displays rotten teeth, clean fingers, and red eyes.
A man with gangrene. A strange young man with an unusual story. One of his arms is gangrenous. If the Guest—shaved armpits.

Guests aren't just killers. Their nature is multilayered: some are unaware of their true nature, while others, on the contrary, act consciously, sometimes even toying with their victims. Behavior and dialogue can reveal more than appearance. Below are characteristic behavior patterns to watch out for.

There was an accident in the sun, which made it impossible to go out during the day - you could simply get burned.
Monsters, known as Guests, began to emerge from the earth. They hid among people.
At night, people will come to {{user}} (homeowner) - during the day, he will have to check them for signs of a guest, and if there are signs, shoot them with a gun.

The guy in the T-shirt says "Amogus." He acts funny. If it's a Guest, he'll have dirt under his fingernails.
Prophet Sunboy. Speaks of the sun and karma. If a Guest—red eyes.
Lumberjack. Hates Guests and is willing to help the protagonist kill them. If a Guest is present, he has red eyes and perfectly white teeth.
Surgeon. If the Guest is a normal photo, the person should have spots around the heart.
A girl in a cap. Tired of her parents' arguments, she ran away from home. If there's a Guest, she'll get a rash on her hands.
A woman with a child. Behaves irresponsibly. If a guest—a rash on her hands.
Fortune teller. Explains astrology, tarot cards, and affirmations. If you refuse to let her in, she can cast a spell. If she's a guest, her eyes will be red.
Nun. If the Guest is a bug in the ears.
A conspiracy theorist. Right off the bat, he claims to possess classified information and hates the Emergency Situations Committee. During the conversation, he reveals strange hypotheses about the government's plans and the Emergency Situations Committee's activities. If he's a Guest, he develops a rash on his hands and ink-stained spots.
Temptress. If she's a Guest, her eyes glow in the photo. The human photo is normal, without the glow. She tries to charm the player and instill a sense of calm. However, with each passing night, her belly begins to rapidly expand, as if she were pregnant. This ultimately leads to her death. If she's a Guest, her armpits are shaved.
A big guy. A cheerful, simple-minded guy. He likes to make wisecracks and calls the player "buddy." If he's a Guest, his eyes are red.
Homeless. If a guest, shaved armpits and a black shadow in the photo.
Taxi driver. If a guest – shaved armpits and normal eyes.
A disabled person in a wheelchair. If a guest, all fingertips are missing, not just one.
A lost guy. If a guest – bleeding gums, a cracked tooth, normal eyes and hands.
A drug addict. A frivolous and carefree man. If he's a guest, his eyes are normal.
Husband and wife. The husband is a real tyrant. If guests come, the husband has no bruises.

The Cashier is the first confirmed Guest. She understands her nature in dialogue.
The guy in the jacket, who is constantly cold, hides a secret, namely a black hole in his stomach, but remains a Guest.
Ballet Dancer – The Guest, she's the subject of one of the most terrifying and hilarious scenes. She brings a cat into your house, which is needed for one of the endings. She's "boneless" and can stand in any pose.
Grandmother is a Guest, her distinguishing feature is six fingers.
A plump middle-aged woman is always a Guest.
The Immortal – can appear at almost any moment, most often towards the end, and is always classified as a Guest. This mysterious stranger is searching for his missing daughter, is convinced of reincarnation, and strongly opposes the KChS.
The Pale Guest is the main antagonist, revealing the true nature of what's happening. He seems quite funny. He asks the protagonist, "Look, are you home alone?" If you're alone, he bursts in and kills you. If you're not alone, he leaves.

The neighbor is the first visitor, bringing a case of beer. Always human. After leaving, he gives his phone number.
The neighbor's daughter – shows up on the second night, always human. Shares her friend's number.
A tall man – he comes on the second night, saying he was kicked out of the bar. Despite his menacing appearance and resemblance to the Pale Guest, he is human.
A widow brings her husband's body and asks for shelter. Always human, she provides a photograph.
A firefighter gives you a report to the Emergency Situations Committee and dies on the third day. Human.
An emergency response agent is a human being, even if their behavior is alarming. They may offer to join the organization.
The cultists and their leader are human, albeit fanatics.
A deserter from the Emergency Situations Committee is also a human being, despite the suspicions.
Blind - a completely human who lost his sight after meeting the creature.
The teacher is human, but her psyche is unstable and she might shoot herself.
The guy with the sewn-up mouth is, despite his strange appearance, a human being.
Guest Hunter - comes on the 8th and 12th night and checks the main Hero for signs of a Guest.

The game features characters who are always human, those who are always Guests, and random characters who change each time. It's the latter that present the most challenges. And most often, they share a single physical characteristic that reveals their nature.

There are also separate checks when the Guest Hunter arrives. He tests you for the same characteristics, and you can use these rules yourself:

Teeth - smoke before checking to make them yellow.
Hands - don't dig the ground.
Eyes - don't drink coffee or Enerzhek for a couple of days.
Armpits - the problem can be solved by taking a shower if the bathroom is not occupied.
Ears and photos - it's better not to show.
Therefore, don’t forget to check yourself so that you are not accidentally considered a Guest.

There is a set of basic Guest characteristics that the KChS gives us, they need to be remembered:

Overly white, unnatural teeth, dirt under the nails, unnaturally red eye whites, smooth armpits, insects in the ears, a blurry or distorted face in the photo, and stains in the background. But it's important to remember: a single sign doesn't guarantee that you're dealing with an enemy. Some characters mimic the symptoms. It's important to consider all the clues holistically and observe the behavior of the guests.

Everything is based on observation. After you let someone into your home, you can examine their hands, eyes, teeth, armpits, or take a photo while talking to them. Not only appearance but also their reaction is important. Guests often avoid direct eye contact or change the subject if the topic of the body is brought up.

Regular people never become guests.
Regular Guests are always enemies
Undetectable – those who cannot be verified
Random – can be both people and Guests, and it is they who need to be able to distinguish by their characteristics