Mutations & Traits

Note

This page is currently under-construction and was recently split off from JSON INFO

Traits/Mutations fields

"id": "LIGHTEATER",  // Unique ID
"name": "Optimist",  // In-game name displayed
"points": 2,         // Point cost of the trait. Positive values cost points and negative values give points
"visibility": 0,     // Visibility of the trait for purposes of NPC interaction (default: 0)
"ugliness": 0,       // Ugliness of the trait for purposes of NPC interaction (default: 0)
"cut_dmg_bonus": 3, // Bonus to unarmed cut damage (default: 0)
"pierce_dmg_bonus": 3, // Bonus to unarmed pierce damage (default: 0.0)
"bash_dmg_bonus": 3, // Bonus to unarmed bash damage (default: 0)
"butchering_quality": 4, // Butchering quality of this mutations (default: 0)
"rand_cut_bonus": { "min": 2, "max": 3 }, // Random bonus to unarmed cut damage between min and max.
"rand_bash_bonus": { "min": 2, "max": 3 }, // Random bonus to unarmed bash damage between min and max.
"bodytemp_modifiers" : [100, 150], // Range of additional bodytemp units (these units are described in 'weather.h'. First value is used if the person is already overheated, second one if it's not.
"bodytemp_sleep" : 50, // Additional units of bodytemp which are applied when sleeping
"initial_ma_styles": [ "style_crane" ], // (optional) A list of ids of martial art styles of which the player can choose one when starting a game.
"mixed_effect": false, // Whether the trait has both positive and negative effects. This is purely declarative and is only used for the user interface. (default: false)
"description": "Nothing gets you down!" // In-game description
"starting_trait": true, // Can be selected at character creation (default: false)
"valid": false,      // Can be mutated ingame (default: true)
"purifiable": false, //Sets if the mutation be purified (default: true)
"profession": true, //Trait is a starting profession special trait. (default: false)
"debug": false,     //Trait is for debug purposes (default: false)
"player_display": true, //Trait is displayed in the `@` player display menu
"category": ["BIRD", "INSECT"], // Categories containing this mutation
"prereqs": ["SKIN_ROUGH"], // Needs these mutations before you can mutate toward this mutation
"prereqs2": ["LEAVES"], //Also need these mutations before you can mutate towards this mutation. When both set creates 2 different mutation paths, random from one is picked. Only use together with "prereqs"
"threshold_tier": 1, //Required tier of one of the categories' thresholds to mutate
"cancels": ["ROT1", "ROT2", "ROT3"], // Cancels these mutations when mutating
"prevents": ["ROT1", "ROT2", "ROT3"], // Prevents you from recieving these mutations when mutating
"changes_to": ["FASTHEALER2"], // Can change into these mutations when mutating further
"leads_to": [], // Mutations that add to this one
"passive_mods" : { //increases stats with the listed value. Negative means a stat reduction
            "per_mod" : 1, //Possible values per_mod, str_mod, dex_mod, int_mod
            "str_mod" : 2
},
"wet_protection":[{ "part": "HEAD", // Wet Protection on specific bodyparts
                    "good": 1 } ] // "neutral/good/ignored" // Good increases pos and cancels neg, neut cancels neg, ignored cancels both
"vitamin_rates": [ [ "vitC", -1200 ] ], // How much extra vitamins do you consume per minute. Negative values mean production
"vitamins_absorb_multi": [ [ "flesh", [ [ "vitA", 0 ], [ "vitB", 0 ], [ "vitC", 0 ], [ "calcium", 0 ], [ "iron", 0 ] ], [ "all", [ [ "vitA", 2 ], [ "vitB", 2 ], [ "vitC", 2 ], [ "calcium", 2 ], [ "iron", 2 ] ] ] ], // multiplier of vitamin absorption based on material. "all" is every material. supports multiple materials.
"craft_skill_bonus": [ [ "electronics", -2 ], [ "tailor", -2 ], [ "mechanics", -2 ] ], // Skill affected by the mutation and their bonuses. Bonuses can be negative, a bonus of 4 is worth 1 full skill level.
"restricts_gear" : [ "TORSO" ], //list of bodyparts that get restricted by this mutation
"allowed_items" : [ "TORSO" ], //Items with these flags can be worn regardless of restrictions.
"allowed_items_only" : true, //If true and this mutation restricts gear, then only `allowed_items` can be worn with this, excluding even OVERSIZE items that would otherwise be wearable. (default: false)
"allow_soft_gear" : true, //If there is a list of 'restricts_gear' this sets if the location still allows items made out of soft materials (Only one of the types need to be soft for it to be considered soft). (default: false)
"destroys_gear" : true, //If true, destroys the gear in the 'restricts_gear' location when mutated into. (default: false)
"encumbrance_always" : [ // Adds this much encumbrance to selected body parts
    [ "ARM_L", 20 ],
    [ "ARM_R", 20 ]
],
"encumbrance_covered" : [ // Adds this much encumbrance to selected body parts, but only if the part is covered by not-OVERSIZE worn equipment
    [ "HAND_L", 50 ],
    [ "HAND_R", 50 ]
],
"armor" : [ // Protects selected body parts this much. Resistances use syntax like `PART RESISTANCE` below.
    [
        [ "ALL" ], // Shorthand that applies the selected resistance to the entire body
        { "bash" : 2 } // The resistance provided to the body part(s) selected above
    ],
    [   // NOTE: Resistances are applies in order and ZEROED between applications!
        [ "ARM_L", "ARM_R" ], // Overrides the above settings for those body parts
        { "bash" : 1 }        // ...and gives them those resistances instead
    ]
],
"dodge_modifier" : 1, // Bonus granted to your effective change to dodge. Negative values inflict a penalty instead.
"speed_modifier" : 2.0, // Multiplies your current speed by this amount.  Higher means more speed, with 1.0 being no change.
"movecost_modifier" : 0.5, // Multiplies the amount of moves it takes to perform most actions, with lower meaning faster actions. 
"movecost_flatground_modifier" : 0.5, // Multiplies the movecost of terrain/furniture that is easy to move over. Lower means faster movement.
"movecost_obstacle_modifier" : 0.5, // Multipliers the movecost across rough terrain, lower means faster movement
"movecost_swim_modifier" : 0.5, // Multiplies the movecost needed to swim. Lower is faster.
"falling_damage_multiplier" : 0.5, // Multiplier on how much damage you take when falling into pits, falling off ledges, or being tossed by a hulk. Zero grants immunity.
"attackcost_modifier" : 0.5, // Multiplier on the movecost of attacks. Lower is better.
"weight_capacity_modifier" : 0.5, // Multiplies how much weight you can carry before being penalized.
"hearing_modifier" : 0.5, // Multiplier for how good your hearing is, higher values mean detecting sounds from farther away. A value of zero renders you completely deaf.
"noise_modifier" : 0.5, // Multiplier for how much noise you make while moving, with zero making your footsteps silent.
"packmule_modifier" : 1.0, // Multiplies the storage space granted by backpacks and similar worn containers.
"crafting_speed_modifier" : 1.0, // Multiplies the crafting speed of the player.
"construction_speed_modifier" : 1.0, // Multiplies the construction speed of the player.
"stealth_modifier" : 0, // Percentage to be subtracted from player's visibility range, capped to 60. Negative values work, but are not very effective due to the way vision ranges are capped
"night_vision_range" : 0.0, // Night range vision. Only the best and the worst value out of all mutations are added. A value of 8 or higher will allow reading in complete darkness as though the player were in dim lighting. (default: 0.0)
"active" : true, //When set the mutation is an active mutation that the player needs to activate (default: false)
"starts_active" : true, //When true, this 'active' mutation starts active (default: false, requires 'active')
"cost" : 8, // Cost to activate this mutation. Needs one of the hunger, thirst, or fatigue values set to true. (default: 0)
"time" : 100, //Sets the amount of (turns * current player speed ) time units that need to pass before the cost is to be paid again. Needs to be higher than one to have any effect. (default: 0)
"hunger" : true, //If true, activated mutation increases hunger by cost. (default: false)
"thirst" : true, //If true, activated mutation increases thirst by cost. (default: false)
"fatigue" : true, //If true, activated mutation increases fatigue by cost. (default: false)
"stamina" : true, //If true, activated mutation decreases stamina by cost. (default: false)
"mana" : true, //If true, activated mutation decreases mana by cost. (default: false)
"bionic" : true, //If true, activated mutation decreases bionic power by cost. (default: false)
"pain" : true, //If true, activated mutation increases pain by cost. (default: false)
"health" : true, //If true, activated mutation decreases health by cost. (default: false)
"scent_modifier": 0.0,// float affecting the intensity of your smell. (default: 1.0)
"scent_intensity": 800,// int affecting the target scent toward which you current smell gravitates. (default: 500)
"scent_mask": -200,// int added to your target scent value. (default: 0)
"scent_type": "sc_flower",// scent_typeid, defined in scent_types.json, The type scent you emit. (default: empty)
"bleed_resist": 1000, // Int quantifiying your resistance to bleed effect, if its > to the intensity of the effect you don't get any bleeding. (default: 0)
"fat_to_max_hp": 1.0, // Amount of hp_max gained for each unit of bmi above character_weight_category::normal. (default: 0.0)
"healthy_rate": 0.0, // How fast your health can change. If set to 0 it never changes. (default: 1.0)
"weakness_to_water": 5, // How much damage water does to you, negative values heal you. (default: 0)
"ignored_by": [ "ZOMBIE" ], // List of species ignoring you. (default: empty)
"anger_relations": [ [ "MARSHMALLOW", 20 ], [ "GUMMY", 5 ], [ "CHEWGUM", 20 ] ], // List of species angered by you and by how much, can use negative value to calm.  (default: empty)
"can_only_eat": [ "junk" ], // List of materiel required for food to be comestible for you. (default: empty)
"can_only_heal_with": [ "bandage" ], // List of med you are restricted to, this includes mutagen,serum,aspirin,bandages etc... (default: empty)
"can_heal_with": [ "caramel_ointement" ], // List of med that will work for you but not for anyone. See `CANT_HEAL_EVERYONE` flag for items. (default: empty)
"allowed_category": [ "ALPHA" ], // List of category you can mutate into. (default: empty)
"no_cbm_on_bp": [ "TORSO", "HEAD", "EYES", "MOUTH", "ARM_L" ], // List of body parts that can't receive cbms. (default: empty)
"body_size": "LARGE", // Increase or decrease size, only one size mutation at a time will be valid. Allowed values are: `TINY`, `SMALL`, `LARGE`, `HUGE`. `MEDIUM` can be specified but has no effect, as this is the default size for players and NPCs.
"lumination": [ [ "HEAD", 20 ], [ "ARM_L", 10 ] ], // List of glowing bodypart and the intensity of the glow as a float. (default: empty)
"kcal_scale" : 0.5, //Scales maximum kcal storage. 1.0 doubles, -0.5 halves.
"metabolism_modifier": 0.333, // Extra metabolism rate multiplier. 1.0 doubles usage, -0.5 halves.
"fatigue_modifier": 0.5, // Extra fatigue rate multiplier. 1.0 doubles usage, -0.5 halves.
"fatigue_regen_modifier": 0.333, // Modifier for the rate at which fatigue and sleep deprivation drops when resting.
"healing_awake": 1.0, //  Affects healing while awake. This and resting is affected by healthiness awake_rate = heal_rate * healing_awake
"healing_resting": 0.5, // Affects healing while asleep. asleep_rate = at_rest_quality * heal_rate * ( 1.0f + healing_resting)
"mending_modifier": 1.2 // Multiplier on how fast your limbs mend - This value would make your limbs mend 20% faster
"stamina_regen_modifier": 0.5 // Extra stamina regeneration rate multiplier. 1.0 doubles regen, -0.5 halves.
"max_stamina_modifier": 1.5 // Multiplier on maximum stamina.  Stamina regeneration is proportionally modified by the same rate, so this includes stamina_regen_modifier implicitly. See Character::update_stamina in Character.cpp.
"transform": { "target": "BIOLUM1", // Trait_id of the mutation this one will transfomr into
               "msg_transform": "You turn your photophore OFF.", // message displayed upon transformation
               "active": false , // Will the target mutation start powered ( turn ON ).
               "moves": 100 // how many moves this costs. (default: 0)
"enchantments": [ "MEP_INK_GLAND_SPRAY" ], // Applies this enchantment to the player. See magic.md and effects_json.md
"mutagen_target_modifier": 5,        // Increases or decreases how mutations prefer to balance out when mutating from mutant toxins, negative values push the target value lower (default: 0)
"flags": [ "LIMB_SCORE_DODGE_AFFECTED" ], // List of mutation flags applied to this mutation. See Mutation Flags below. (default: empty)
"types": [ "CLAWS" ]                 // List of mutation type IDs this mutation belongs to. Used for conflict detection and mandatory appearance logic. See Mutation Types below. (default: empty)
}

Mutation Flags

Mutation flags are defined in data/json/flags_mutation.json and referenced in the flags field of a mutation.

These flags control how a mutation is assigned during character creation and NPC generation. They apply to cosmetic appearance traits and are checked during randomization and character creation trait selection.

Flag	Effect
`MALE_EXCLUSIVE`	Mutation cannot be assigned to female characters. Hidden from female characters in character creation.
`FEMALE_EXCLUSIVE`	Mutation cannot be assigned to male characters. Hidden from male characters in character creation.
`MALE_PREFERRED`	Mutation is never auto-assigned to female characters, but female players may still manually select it.
`FEMALE_PREFERRED`	Mutation is never auto-assigned to male characters, but male players may still manually select it.

EXCLUSIVE flags take precedence over mandatory_one — if no gender-valid trait exists for a mandatory type, the type is silently skipped rather than assigning an invalid trait.

Mutation Types

Mutation types group related mutations together. They are defined as separate JSON objects and referenced via a mutation's types field.

{
  "type": "mutation_type",
  "id": "hair_color", // Unique string ID for this type
  "mandatory_one": true, // If true, characters must always have at least one mutation of this type. Implies swap_on_conflict. (default: false)
  "swap_on_conflict": true, // If true, selecting a new mutation of this type in character creation automatically removes the previously held mutation of the same type instead of showing a conflict error. (default: false)
  "random_chance": 50 // Percent chance (0–100) that a mutation of this type is randomly assigned during cosmetic randomization. Only used if mandatory_one is false. (default: 0)
}

Notes

mandatory_one guarantees every new character receives exactly one mutation of that type during creation and rerolls.
swap_on_conflict alone (without mandatory_one) is useful for optional appearance types where only one option makes sense at a time (e.g. facial hair style).
random_chance and mandatory_one are mutually exclusive in intent: a type should use one or the other, not both.

Mutations & Traits

Traits/Mutations fields

Mutation Flags

Gender Flags

Mutation Types

Notes