AI System

Cannibal using pathfinding techniques to complete their tasks in the most efficient manner possible.

In Sons of the Forest, the artificial intelligence system for each living entity is designed to provide a dynamic and evolving experience for players. This is achieved through a set of cognitive capabilities known as "thoughts," which generate paths for each entity based on a variety of variables that adapt and evolve in response to the player's actions and decisions. To achieve this level of complexity, the game's AI system uses a ruled-based modeling approach, which allows for the pre-programming of specific rules and constraints that guide the entities behavior. Each entity within the game is categorized based on their name, emotions, fear, anger, and energy levels which significantly influence their interactions with the player.

Although this type of information may not be visible to the player, it plays a crucial role in comprehending the game's artificial intelligence system. By leveraging ruled-based modeling, the Developers are able to create a rich and immersive experience that provides players with a dynamic and evolving gameplay experience.

Entities

Name

In most cases, an entity's name corresponds to its model or characteristics. For example, Moose, Turtle, MuddyMale, and MuddyFemale are simple names used to identify entities lacking complex features. However, the naming for regular Cannibals differs, as they may be referred to as Carl, Andy, Angel, Billy, Danny, Brandy, Crystal, or Destiny. The origin behind those names remains unknown.

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  Angel

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  Danny

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  Andy

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  Billy

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  Carl

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  Destiny

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  Brandy

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  Crystal

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  Goldmask

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  PaintedMale

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  Muddy Female

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  Muddy Male

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  Fat Male

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  Fat Female

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  Heavy Male

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  Faceless Male

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  Fingers

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  Baby

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  Demon

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  Demon Boss

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  John2

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  Mr.Puffton

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  Mrs.Puffton

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  MrPuffy

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  Miss Puffy

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  Slug

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  Timmy

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  Robby

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  Virginia

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  Moose

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  Rabbit

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  Squirrel

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  Seagull

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  Eagle

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  Duck

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  Deer

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  Land Turtle

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  Turtle

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  Humming Bird

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  Bluebird

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  Shark

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  KillerWhale

Sentiment

Example of Sentiment with Cannibal

Sentiment plays a crucial role in Sons of the Forest, it's influencing how the Cannibal AI remembers past interactions with the player. The only way of decreasing sentiment towards the player amongst entities involves causing them damages through any means possible. If a Cannibal endures severe injuries and remains alive, its negative sentiment towards the player will persist for an extended duration. Notably, entities such as the Golden Mask Cannibal maintain their sentiment towards the player, even if they are subjected to attack from the player. While the full extent of sentiment's effects remains uncertain, it currently serves no practical purpose within the game. However, there is a possibility that the developers will allow players to establish friendly relationships with certain Cannibals or tributes in the future. As of now, sentiment levels will only increase if interacting with Kelvin or Virginia.

The sentiment level of Kelvin gradually increases by approximately 0.1 every seven seconds when in proximity to the player.

The sentiment level of Virginia gradually increases by approximately 0.1 every seven seconds when in proximity to the player.

Fear

Example of Fear with Cannibal

When (Fear value) ≥ (Anger value) it prompts entities to flee from a player. E.g. a cannibal with 100 anger will not flee in fright until it gets 100 fear. Fear levels can be increased by effigies, taunting with equipped skulls/heads, causing damage, and gunshots.

Player-influenced fear can be interpreted as a rational behaviour which varies from different entities. For instance, Dirty cannibal normally begins with 30 of fears, in contrast to a normal Cannibal who starts at 0.

The best way to comprehend fear is by comparing it to human stress during a fight. The fear level of a Cannibal, for instance, may start at around 20 during a fight, but can quickly increase to 100 if it gets hit. During such situations, fear levels tend to fluctuate frequently, rising and falling in response to changing circumstances.

To see debug information regarding fear and anger use the command "aishowstats on".

Anger

Example of normal anger with Cannibal

The most influential variable among the bunch is anger, which directly affects entities within the game. Essentially, anger represents the probability of a cannibal attacking the player. Although this variable is not fully understood, it is established that the initial anger level of cannibals at the start of a game is 10 towards the player, which increases based on the player's actions throughout the game. Actions such as destroying villages, killing cannibals, being in a village camp, being in close proximity to cannibals, cutting trees, and shooting either at cannibals or in general can all contribute to an increase in the anger level. Once it reaches 100, cannibals will exhibit aggressive behavior and will actively pursue and attack the player. As of now, there is no way to decrease this variable. Consequently, players cannot maintain peaceful relationships with any clans or cannibals.

The game employs three types of anger levels, which are player-influenced, environment-influenced and anger in general. The former is determined by the actions of the player, while the latter is determined by various environmental factors, such as the presence of enemies or perceived threats. These anger levels are known to fluctuate frequently, rising and falling in response to changing circumstances. When it come for the general anger of the cannibal for the entire game, Regarding the general aggression level of cannibals throughout the game, it is determined by the number of cannibals killed by the player and the current day in-game. However, there are certain methods, such as utilizing molotovs or bombs, that do not directly contribute to the increase of this variable. As the aggression level increases, so too does their armor rating. Consequently, it is imperative to consider their impact on entity behavior while playing the game.

In the most recent update, the developers have calibrate anger levels for certain entities of the muddies cannibal. It appears that the anger levels for this entity have been reduced from 10 to 6, resulting in a decrease in their level of aggression. In the foreseeable future, we anticipate that such changes to entities behavior may become more frequent. As a result, we plan to make a board to monitored all entities when it will be necessary.

Energy

Energy can be considered as a variable that is shared between the player and other entities in the game. This parameter is crucial in providing a realistic experience for the entities, as it introduces a sense of vulnerability and limits their endurance, similar to that of the player. With each movement, an entity loses 0.1 units of energy. However, certain entities such as the golden cannibal may deplete their energy reserves at a faster rate, especially when charging at the player. Depending on the type of attack, the energy loss for an entity can range from 2-3 units for a slash, to 6-9 units for a powerful strike.

Kelvin cutting a tree with his energy levels depleting rapidly.

In addition, Kelvin, one of your companions in the game, is also affected by this variable. His ability to perform tasks and assist the player is directly impacted by his energy levels. For instance, cutting down tree in quick succession can cause him to lose up to one energy level per second. Once he has finished the task, Kelvin will take a break and rest to gain energy levels. Despite Kelvin having a limited amount of energy, he is capable of continuing to perform tasks even when his energy levels have been depleted to zero.

Kelvin resting to increase his energy.

Memory

Example of memory with Cannibal

Memory is an important component of an entity's decision-making process because it enable entity to recall past actions. However, not all interactions and events can be stored in memory, as it would require significant computational resources. Instead, only important events and interactions that have a significant impact on the entity's behavior are recorded and retained in memory. This includes fighting regular cannibal, fighting muddies, fighting Creepies, hunting animals, getting sticks and firearm usage by the player.

Each entity's memory value decreases by 0.01 every 3 seconds, which means that the impact of past events and interactions on an entity's behavior decreases over time. However, the memory value will stops decreasing once it reaches a certain threshold, which depends on the frequency and intensity of the observed actions of the player. For instance, when a player attacks a village and engages in combat with a member of a cannibal family, the event is recorded in the memory of the entire family and influences their behavior towards the player. It is important to note that if the player fights a certain type of cannibal close to other types of cannibals, this event will be recorded in their memory and will have a lasting impact on their behavior.

A point to note is that Cannibals in the game will not remember if you spare them or their injured family members. However, they can retain other values such as fear and sentiment towards the player. It's important to consider that these entities are not capable of complex emotions or thought processes beyond what is programmed into their AI. So, while they may exhibit certain behaviors and responses, they do not have true memory or consciousness like a human being.

Stats

The variables referred to as "stats" are integral to the behavior of all entities. However, the current implementation of this variable is incomplete and requires further refinement from the developer as it has little impact on their behavior. As of now, Entities are not penalize for having low values for their stats. The statistics are categorized into three main components: fullness, hydration, and energy.

Fullness will varies depending on the entity's food intake. For example, cannibals exhibit little to no fullness and rely on consuming body parts to replenish their fullness levels rapidly. Although they seem to exhibit hunting behavior, it has yet to be observed in action. In contrast, animals such as birds display more apparent fullness behavior, as they actively seek out sources of food and water. The seagull is a notable example of this, as it will land to consume something on the ground, even though it cannot be interacted with. Fullness levels decrease by 0.1 for every entity every 2-3 seconds.

Hydration levels are essential to the survival of all entities and can be replenished by consuming any available source of water, including cave water for the blind mutants. Hydration may become more apparent in the future as it has the potential to significantly impact the behavior of entities if not consumed. Currently, however, it is not a requirement for entities to consume water and does not have a significant impact on their behavior. While cannibals may occasionally be observed consuming water from a nearby body of water, it is not a priority for them. As of now, hydration levels decrease by 0.1 approximately every 0.7 seconds.

Status

Each entity within the game has a permanent status that communicates its current actions to the game in real-time. These status are categorized based on their specific meanings, which can vary depending on the entity's current situation. The following are all of the possible status:

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  Flying

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  Combat

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  Sleeping

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  Exploring/interacting world

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  Captured

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  Dead/Dying

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  Underleaves

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  Swimming

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  Injured

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  Burning

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  Electrocuted

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  Onrock

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  Leave Combat

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  On tree

Thoughts

In AI, thoughts are essentially programmed decision-making processes that determine an entity's behavior in response to various environmental factors. In other word, They are essentially set of rules or instructions that the AI of entity will follow for their next action(those rules are designed to be flexible). Since there are numerous factors that can influence an entity's behavior, there are countless thoughts that can occur. These thoughts are often programmed with a degree of randomness, to make the entity's behavior appear more natural and unpredictable.

Full List

To facilitate a comprehensive understanding, I will make a list of all thoughts an entity may possess by their status:

Exploring/interacting world

Taunt Captured!	What was that noise?	Rest a bit	Explore the world	Heard something near	Loud sound! Go check it out
Check my hut	Startled by loud noise	Idle fidget	I should explore the world	Someone is right near me	Mourn [name]!
Pray a bit	Mourn my Dying LOVE!	Flee from noise	Go to Drink Water	Move to forest	Run from enemy!
I heard something close	What was that sound?	Eat my friend [name]	Run, very close sound!	Run away from enemy!	I should get outta here
Sit by fire	Throw that body	Hit by projectile	Land	I need some time alone	I should bash this [name] head
Go back to base I'm hurt	Time to sleep	Enjoy the view.	Search for water	Hide against wall	Drink water
Explore the area	Hit by melee	Create a nest	Follow [baby]	I'm bored	Just standing arround
Waiting for interaction	Waiting for note	Pickup sticks	Drop sticks	Search party move	Wait to see if enemy appear
I should fight	Waiting by Player	Hide crouched	Follow Player	Flee From LocalPlayer	Eat Food
Shelter at hut	Cower in fear	Go to food	SeveredArmsPickup	Taunt the muddy	SeveredHeadPickup
I'd check if this [name] is ?alive?	Flee from Cannibal	ouch I got hit	Go Hunt as Group	Pray to mask man	Head Home
Step curious to mask	I should eat food	Steal that log	Bash this structure	Climb reaction	Hit the muddy!
Taunt [Name]	Search for lost enemy	Rub my feet	Go to food	Go to water	Dance on tree
Wash in water.	Laugh with player	Player is stopping me.	I like that, thumb up	Drop items	Eat [Name]
Wash in a waterfall.	Get Player to follow me	Lead Player	Dance to this music	Grab a radio	Follow player with radio
LocalPlayer is too close.	Lound sound! Flee area	Move near player	Move away from player	Gather some berries	Search this bush

Combat

I see an enemy to fight	Jump onto rock	Jump off rock	I like to watch crouch	Step curious toward enemy	Run back from target !
Idle watch	Approach enemy	Step back slowly	Taunt [Name]	Jump onto Tree	Jump off Tree
Run to Flank target	Flank target	Circle LocalPlayer	walk to Flank target	Leave Search area	Back away from enemy
Anticipate dodge	Attack react	Walk flank back	Combo Attack React	Big Taunt LocalPlayer	Move to Attack
Gun run!	Throw that body	Run kick LocalPlayer	I'm drowning	Too far from trees!!	Flee the area scared!
Run attack LocalPlayer	Jump attack off rock	Move closer to ATTACK	Jump attack LocalPlayer ne?	Hide behind a tree	Argghhh I tripped
Threaten LocalPlayer	Throw rock at LocalPlayer	I should fight	I should run back	Run attack in out	I should combo attack
To attack Localplayer from behind?	Move to last sighted point	Im feeling better now	ee? scared from LocalPlayer	Run kick Robby	Alert others I saw someone?!
Run from [name]!	Lunge attack LocalPlayer	Taunt Robby	Threaten? LocalPlayer to stay ?away	Run attack Robby	Distracted by food
Ouch I got hit	Dodge and counter	Flee Scared from LocalPlayer	I like to watch	Step back slowly	Watch enemy
Back Away	Point at [Name]	Cower in fear	Block PlayerMeleeAttack	Block ancitipate	Watch enemy far
I should fire at enemy	Move away from enemy	Aim weapon at [Name]	Back away quickly	Run behind a tree	Point at this enemy
Pistol shot this guy!	Shotgun this fool!	Attack from tree	Block to counter	-	-

Dying/Dead

Im dead	Oops I died radgoll	I should crawl back	I'm dead an limp.

Flying

Explore the area	Fly near player	Find food and land	Flee from soft noise	I should land	Flee from noise	Eat this while flying
Hover Dart	Circling arround that	Flee medium noise	I should go fly around	Explore the world	Fly away to sleep

On rock

Watch LocalPlayer	Ouch I was Attacked!	Jump out at enemy

On Tree

Hang out in tree	Jump off tree	Taunt LocalPlayer	Jump to new tree

UnderLeaves

Jump out by [Name]	Ouch I was Attacked!	Jump out at enemy

Injured

Just staying here.	Flee area, I'm injured!	Flee from LocalPlayer	Im so tired	Should enter injured states

Behavior

Each entity exhibits a unique and distinct behavior. To gain insight into those behaviors, understanding and analyzing their patterns is necessary. In the following section, a comprehensive presentation of each entity present in the game will be provided, along with a detailed analysis of their observed behaviors in-game:

TBA

Turtle

The reptilian entities tend to remain in offshore with occasional forays onto land for purposes such as exploration or laying eggs. Their behavior is relatively simple, lacking complexity and they do not display any signs of attempting to seek food or water. Furthermore, they appear to be free from predation by Cannibal entities. It is worth noting that when their eggs hatch, baby turtles emerge which cannot be interacted with or harmed in any way, and thus, do not qualify as a separate entity.

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  Exploring the land

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  Fleeing to water

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  Swimming to land

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  Swim Explore