In the intro sequence the player wakes up in one of the Class-D cells, If you are playing alone you can prefer yourself as "D-9341" but if you are playing CO-OP version of the game you can choose whatever nickname you gonna give yourself, in the Class-D cells you can find a Document in your personal table, explaining the Facility and tasks you are gonna do in the future, after picking up the document the door opens and 2 Facility security guards are gonna force you to comply stepping out of the cell. if you don't comply within 3 Threatening the guards will close the door and Gas you to death, If you do comply the game truly begins, You are tasked with following the guards till you reach SCP-173 Containment Chamber, once you arrived at the called "SCP-173" you are greeted with a loud Mic echoing forcing you to enter the chamber doors, within inside the chamber you can find SCP-173, you are not alone as you are with 2 other Class-D, 1 one bald and the other one is black.
Once SCP-079 briefly flickers the Facility Main Power Lighting System you cannot see SCP-173 with your 2 Other Class-D friends, SCP-173 instantly kills them both since you can't see SCP-173.

When the player survives the first encounter with SCP-173 they can leave the chamber, The doors to his D block Cells are locked down because of the Containment Breach so the player has to go down, as they lower down the player can see 2 Facility staff each one with a Facility guard and a Security chief with SCP-173 in front of them, when the lights flicker again because of SCP-079, SCP-173 briefly sees you but has empathy since SCP-173 is busy with 2 other dudes. After the sequence is finished you can finally head out to the Facility, Once you open your inventory (TAB by Default) You can remove the 2 documents you have acquired since they become useless but if you don't know any SCP-Lore or any SCP Genera I recommend reading it.

SCP-173 is the first SCP object that the player encounters. At the start of the game, D-9341 is taken from his cell along with two other class-Ds to perform testing on SCP-173. However, during the testing, the site undergoes a power failure, allowing SCP-173 to kill the two class-Ds and a guard before escaping into the ventilation system.

Once the containment breach has started, SCP-173 first appears in the office connected to its containment area. Security Chief Franklin can be seen warning Agent Ulgrin about SCP-173 being behind him. Ulgrin will then turn around and start backing out of the room while they both continue to stare at SCP-173. Once they leave the room, a brief blackout will occur, allowing SCP-173 to escape.

Throughout the game, SCP-173 will follow and attempt to kill the player. If the player does not blink or look away from it, SCP-173 cannot move. If the player breaks eye contact, SCP-173 will either move significantly closer to them or open any doors that are blocking its way. Its movement can be noticed by the stone scraping sounds it makes while travelling.

SCP-173 can spawn in any room of the facility. It commonly appears in lockrooms, gas catwalks, server farms, the small testing room, and sometimes in the metal corridors. Rooms that it can suddenly appear in typically have a broken ventilation shaft cover in the room.

SCP-173 will also appear in the storeroom. As soon as the lights in said room go out, SCP-173 will break through the vent and kill a scientist and a janitor discussing escape routes.

If the MTF operatives encounter SCP-173, they will proceed to prioritize re-containing it, ignoring the player if present unless approached directly. When an operative needs to blink, they will announce it before doing so in order to prevent SCP-173 from moving. The operatives will then use a containment box to capture SCP-173 and return it to its containment chamber.

SCP-106 is a mobile threat, and appears quite often. It can spawn at any time near the player (either from the floor or from the ceiling). Once SCP-106 has spotted the player, it will immediately begin to pursue them. SCP-106 is difficult to deter, due to it being able to phase through doors, with the only way to shake it off being to wait out its pursuit for an amount of time or trick it into walking into a Tesla gate, stunning it and causing it to retreat. Should the player wander too far from SCP-106, it will teleport closer to them. If the player attempts to pause the game while being chased by SCP-106, the game will quickly unpause with the message "STOP HIDING".

If SCP-106 manages to catch the player, it will take them to its Pocket Dimension. At the first intersection, SCP-106 will wander around this room in a counter-clockwise pattern through the walls of the hallways. Physical contact with it in this dimension results in instant death. After it performs 3 full rotations around the map it'll head straight towards the player if they are still in the intersection.

SCP-106 appears again in the pillar area. SCP-106 will be floating upside-down a few pillars away and will teleport to adjacent pillars, coming closer to the player. Every time SCP-106 teleports, the player is forced to blink.

In the throne room, SCP-106 will be perched atop a large throne-like column. The player is only able to see its eyes and upon approaching the throne, the camera is forced up in its direction. Staying too long in the room will cause a deep voice (possibly that of SCP-106) to tell the player to kneel.

Once the player enters the monitor hub portion of the surveillance room, SCP-049 will follow shortly after in pursuit, due to SCP-079 reopening all the keycard locked doors. When within range, SCP-049 will extend its arm and attempt to catch the player. It is advised that the player avoid SCP-049 as much as possible. SCP-049 is no faster than the player's walking speed, but it is very persistent and will not be deterred by Tesla gates. The player's best hope of escape is to lock SCP-049 behind a security checkpoint, or hide behind a door connected to a junction and sneak away while SCP-049 searches the other rooms.

When traveling through its containment chamber, the area's power will malfunction, and the lights will go out, forcing the player to manually activate the generator and re-route the elevator's power to the generator. Upon reaching one of the now-re-activated elevators, SCP-049 will emerge from the elevator that the player gets in close proximity to. The player should quickly run around SCP-049 and escape through the elevator, as it is very easy to become trapped between it and the SCP-049-2 instances.

SCP-049 can also occasionally be seen on the unreachable catwalk in the four-way hallway, although it has no way of reaching the player. In addition to these encounters SCP-049 will randomly patrol the facility and pursue the player should they encounter it.

If SCP-049 manages to gain physical contact with the player, they will fall over and die. If this happens in SCP-049's containment chamber, a scene then plays out depicting the player, now an instance of SCP-049-2, hobbling towards three Nine-Tailed Fox members. Shortly after, they will start shooting the player, killing them.

If the player is wearing SCP-714 or a Hazmat Suit, SCP-049's touch will not cause the player to die instantly. However standing in front of SCP-049 for too long (5 seconds for SCP 714, 10 seconds for the hazmat suit) will result in the ring or suit being taken off, making the player vulnerable to SCP-049's touch.

In Light Containment Zone this is where you begin the game. First you thing to do is to get a Level-0 Key-Card from 2 infinite closet room or the SCP-173 Bridge room, Once you get a Level-0 Key-card you can find a Janitorial Closet door, Opening it you can find a Level-1 inside, the Level-1 is bad but its your most important card, You can find a "Light Testing Chamber 2B" room, opening it with a Level-1 Key-card you can enter the room, inside it is there a Level-2 Key-Card aswell a S-Nav, But you have to look directly to SCP-173 as he always spawns in the room, Blinking once will make him Teleport in the room you are in breaking the glass as well, after getting a Level-2 Key-card you can find SCP-914.
inside SCP-914 you can put your Level-2, and other loots in "Fine" Settings and roll the clog below it, in the other side of the room the results can come out, The key-card can turn into Level-3 key-card and for the Gas-Mask you can put it on "Very Fine" settings to have more Stamina when you put it on. Once you have a Level-3 Key-Card you can find a Surveillance Room which is only accessible with a level-3 Keycard, Once you enter it you need to turn off Light Containment Zone lock-down up in the Security room, but when SCP-049 enters the room you need to crouch and be in the opposite side of the table so the SCP-049 cannot see you, after some time when he leaves you can go away and unlock the Heavy Containment Zone lockdown.

When you enter Heavy Containment Zone the first thing you gotta do is to find SCP-049 containment chamber lifts, once you find it you can enter it, once you enter it the Rooms light system goes into a black out, You have to find the lever to activate the emergency lighting system, once you locate it and turn it on the SCP-049-2 Subjects will be activated and start hunting you down, inside SCP-049 chamber you can find a Level-4 Key-Card which you can have, (You can remove all of the old Key-Cards if you want), Once you acquired the level-4 Key-Card you can turn on the generators so the lifts can run again, Go back to the lift you came from and activate SCP-049 spawning, and go to the Other side of the place and reach the other lift, if its a dead end you have to go back. Once you acquired the Level-4 Key-card find SCP-106 containment Chamber and Activate the Femur BreakerAfter you get the Level-5 Key-Card you can finally go to SCP-008 containment chamber and disable its containment Breach, it will unlock the Entrance zone lockdown.

Once you have entered the Entrance zone Mobile Task Force epsilon-11 designated the "Nine Tailed Fox" will spawn in the facility as they contain SCP's and Eliminate Class-D Subjects such as you, so you gotta be cautions around them, If you get shot in the head you will die instantly. Once you play hide and seek with the NTF you can find the Electrical Center room, Inside you need to disable the Remote door controls and enable secondary lighting lever, once you have done all of this go back to SCP-079 Chamber and confront him, once he gave you tasks to re enable the Remote door controls go back to the electrical room and do as if he says, Once you have done go to Gate-A and finally escape, There you are, in the surface.