The Monster behaves similarly to the Alien: Isolation. It will react accordingly to the player's actions such as what noises are they causing and what kind of noises. It is fairly capable to kill players instantly in one hit but may sometimes just wound them instead in some cases.

It can be scared of through various ways but that will only anger it, making it stronger in the end.

The Monster will react to any noise the player will cause at any point throughout the game's playthrough. There are almost no scripts to force-spawn the Monster, it is almost completely independent and will behave on its own accord. The only exception to this is when you enter the Chapel for the first time as the monster will spawn and enter the Chapel in response when that happens.

Even if you cause the following noises, the Monster might not always emerge when there are actively powered lights in the area.

Let's talk about the noises. I'll name them two types of noises; Quiet and Loud.
The following are considered quiet noises;
- Cranking up the flashlight.
- Running.
- Tossing objects.
- Tossing empty bottles.
- Flares.
- Slamming doors.
- Artillery explosions.

The following are considered loud noises;
- Gunshots.
- Explosions.
- Destroying doors.
- Prisoner yelling.


If a quiet noise is done, the Monster may or may not emerge from a hole. Causing quiet noises will only increase the random chances for the Monster to emerge and is not a guarantee that it will definitely come out.
For example, running for two seconds is not a guarantee that it will emerge but the more you run, the higher chances it will emerge. The same goes for how many times you crank your flashlight in a row. You only need to crank it twice.

On the other hand, if a loud noise is done, the Monster WILL most likely emerge. So, if you shoot a keychain or whatever, seek a hiding spot. You may hear the Monster crawling into a wall before emerging from a hole.

When either noise is caused and the Monster emerges, they will investigate the source of the noise. Whichever hole they seek to emerge, it'll be the closest to the source of the noise.
How long the Monster will investigate seems to be dependent on how many and how loud the noises were. If an explosion was caused, it may take up to a minute. If two explosions, it could be two minutes.

In either case, the Monster emerging does not mean they are fully aware of your presence just yet.
When the investigation is completed, the Monster will enter a hole again, making it safe for the player to travel. You may hear the Monster crawling elsewhere.

Certain actions do not seem to cause any noise such as pulling in or out the flashlight and any other item so you are safe to do those.

The Bunker is full of holes. Fortunately or unfortunately for you, the Monster uses those holes to emerge and roam freely or investigate noises. They are its main ways to navigate through any part of the Bunker effortlessly. You, in the meantime, have to find keys to unlock doors in order to navigate through the Bunker. You - 0 Monster - 1.

At times, you can hear the Monster crawling through the ceilings and into the walls. You can see dust falling from the ceiling which is usually an indicator that the Monster is crawling or just crawled before it stopped somewhere. Do not confuse the falling dust from the random artilleries that land outside the Bunker.

When a noise is caused, usually quiet ones, the Monster may crawl to the nearest hole where the source noise is caused and stay. When that happens, you'll see dust coming out from the hole constantly. Walking through an active hole or standing next may result in the Monster snatching you into the hole, killing you instantly. It may sometimes surprise you by emerging out of the hole, injuring you in the process and knocking you out for a moment.

When a hole is active, some nearby lights may start to flicker at a slow pace.


Holes can be blocked with a heavy object. Doing so will prevent the monster from emerging from that hole and will try to emerge from other holes in the vicinity instead. However, heavy objects may break on further attempts if the Monster keeps trying to emerge from a blocked hole.

Having the lights powered on by the generator may decrease the game's difficulty in some ways and can be a lifesaver. Having the lights off will plummet the entire bunker into pitch darkness which not only makes your navigation in the bunker difficult but it permits the Monster to roam freely for any reason and that's bad news for you.

With the lights powered on, the Monster will not roam freely in powered areas. Instead, it will remain in the holes. It will, however, emerge if you cause enough noise. When that happens, lights near the monster will start to flick rapidly. This is your cue that the monster is definitely near the spot where the lights flick rapidly. Distant lights will flick slowly. This is why the lights can be a lifesaver because they give away the Monster's rough position.

With the lights off, the Monster will roam freely at any time for any reason and, sometimes, may not return to holes. Furthermore, it will most likely emerge from holes when a noise is caused in contrast to powered areas where it might not appear at all sometimes.

Using explosions can destroy nearby lights, rendering those areas dark for the Monster to roam freely so be careful.

(Credits Ⓙⓐⓒⓞⓑ for the picture)

Initially, the Monster will not appear in the game until you pick up the red wheel crank. It will only stay in the holes instead, trying to snatch unsuspecting victims. Once the red wheel crank is picked up, it'll start emerging accordingly to noises or dark areas. This rule does not apply on the second playthrough as it'll emerge before the red wheel crank is picked up.

The Monster will emerge in dark areas on its own accord. During a patrol, it may destroy any object on its path apart from metal doors as it will try to open them instead if they are unlocked, including the doors at the save room. If they are opened, it'll freely enter that room and the generator room. Heavy objects require a few attacks before they are destroyed.

It can see you at long distances and, when spotted, will stand up on its legs and roar before breaking into pursuit. This will give you plenty of time to react and flee or defend yourself.

If it catches you, there's no way to avoid its grasp as it can overpower you and kill you.
It may sometimes injure you instead such as emerging from a hole when you are near one or by randomly throwing you away.

There are a few ways that you can defend yourself; Shooting at it, using gas grenades, using fire or using any explosive items. In normal circumstances, injuring it will cause it to flee into a hole and leave the area temporarily. However, this will only make it angrier the next time you encounter it. This also means that further defenses will not work efficiently.

Depending on the game's difficulty, the Monster will always flee on the first gunshot in EASY mode. In NORMAL mode and higher, the defensive tools become useless the more times they are used on the Monster. For example, in NORMAL mode, it will flee on the first gunshot. However, the next time it comes back, up to 3 gunshots may be required to force it to flee and so on. In HARD mode, you may need two shots on the first time.
The Monster can walk up to traps (that were set up by former soldiers) and get injured by itself in the process. It will flee when that happens.

In EASY mode, after fleeing, it may take up to 10 minutes before the Monster emerges again. Until then, it will be hiding in the holes, waiting to snatch unsuspect victims. In NORMAL mode and higher, after fleeing, the Monster will emerge again after several seconds.

If the Monster loses sight of you, it will go to the latest spot that the noise was caused (ie. running before you stopped running). It'll then investigate the immediate vicinity and may break down doors, tables, etc. The Monster is also capable of going through vents as well.
During the investigation, the Monster may stand idle as if it's trying to listen for any noise you may make (ie. cranking flashlight).

If you are injured, the Monster can smell your blood and easily track you.
The Monster is incapable to learn anything new. It will, however, catch up with you if a pursuit prolongs too long.