1.1 Scales

A tile of the world grid covers 1° of longitude and latitude, about 111 km at the equator. In local view, each world tile is subdivided into 64 × 64 local tiles: a local tile is therefore about 1.7 km across. The character, individual animals and buildings exist only at this scale. The grid wraps from east to west; it is bounded to the north and south.

 WORLD (1 tile = 1°)      REGION                 LOCAL (1 tile = 1.7 km)
 ┌─┬─┬─┬─┬─┐            ┌────────┐             ."".:.;..  ♣♣♣♣
 ├─┼─┼─┼─┼─┤            │ 8 × 8  │             ..@.,.♣♣♣♣♣♣
 ├─┼─┼█┼─┼─┤   ──►     │ blocks │   ──►       ~~≈≈..♣♣"""",
 ├─┼─┼─┼─┼─┤            └────────┘             ≈≈≈..""""∴∴
 └─┴─┴─┴─┴─┘      one world tile = 64 × 64 local tiles

1.2 Generation

The stages run in this order; each has its own stream of random numbers, so changing one stage does not alter the randomness of the others.

  plates ──► relief ──► oceans / sea level
                │
                ▼
   temperatures ─ winds ─ currents ─ precipitation
                │
                ▼
   runoff ──► rivers, lakes
                │
                ▼
   classification of each tile ──► biome + fertility

The classification of a tile combines mean temperature, extreme temperatures, annual precipitation and seasonality, elevation, local relief, distance to the coast, the presence of rivers, lakes and volcanoes, and substrate noise. It is inspired by the Whittaker and Köppen classifications. A majority filter then smooths out isolated tiles.

1.3 The 37 biomes

Table 1.3 is produced from the game modules: identifier, map glyph and colours, movement cost for walkers (speed multiplier), natural shelter, permanent presence of small water sources, and capacity for each vegetation type (0 to 1). The last column summarises the classification criteria.

1.4 Hydrography and plates

River glyphs follow the direction of flow: ─ (east-west), │ (north-south), ╲ and ╱ (diagonals). Lakes are salt or fresh depending on whether the basin is closed.

1.5 Vegetation and habitats

Animal species are spawned per ecological region. Each region groups several biomes:

2.1 Clock and calendar

Tick

1 tick = 5 game minutes (12 ticks per hour).

Day

24 hours, i.e. 288 ticks.

Year

360 days, i.e. 103,680 ticks.

Start

Life starts at the northern spring equinox (year fraction 0.25).

Seasons

Hiver, Printemps, Été, Automne. The season depends on the hemisphere: in the south, the phase is shifted by half a year.

2.2 Local day and night

Solar time depends on longitude: it differs from the reference time by 24 h × (x − width/2) / width, where x is the column of the tile. Two columns a quarter of the world apart are six hours apart. Night is determined per tile; the light perceived by the character is the average of three neighbouring columns (0 = full night, 1 = full daylight).

Day length depends on latitude, date and axial tilt (23.5° by default):

Beyond the polar circle, the sun does not set in summer and does not rise in winter.

2.3 Simulation speeds

At speed ×1, game time flows at 10 game minutes per real second. The other speeds multiply this rate. If the machine cannot keep up, the time actually achieved is shown in the time bar.

2.4 Turn-based mode

In turn-based mode (T key), the simulation is paused and only advances when the player acts. A timed action consumes its ticks. A character step consumes a number of ticks derived from the step duration: on open ground, a step lasts 120 ms in real time and is worth 2 ticks (10 minutes); the number of ticks is rounded from 2 × (terrain cost) × (√2 diagonally) × (slowdown), clamped between 1 and 8. Waiting (Space) consumes 1 tick.

  turn-based              real time
  ─────────────           ──────────
  step ─► +2 ticks        clock ─► continuous ticks
  action ─► +N ticks      actions run
  Space ─► +1 tick        while time passes

3.1 Game modes

Switching from Survival to God sets the survival inventory aside; it is returned when you switch back. After a death, continuing in God mode and then returning to Survival starts a fresh life: full needs, empty inventory apart from the starting provisions.

In God mode, the God tools panel (Shift + O) lets you spawn animals, plants and tribes on the clicked tile, and trigger climate events. An animal only appears in a habitat that suits it (otherwise the tool refuses and says so); a tribe camp is placed exactly on the clicked tile. Animals remain selectable while paused and the tribe list refreshes even when the game is stopped.

3.2 Gauges

Five gauges describe the body. The character weighs 70 kg. At birth: 2,250 kcal out of 2500, water 90, warmth 60, rest 90, health 100. Starting provisions: 8 × fruit and nuts, 6 × seeds.

3.3 Felt temperature

The body reacts to the felt temperature: air temperature plus clothing and fire, minus wind and rain, plus shelter. Wind only cools below 22 °C; shelter softens wind and rain.

Only the best garment in each slot (body, feet, head) counts; the values add up. Body warmth tends towards an equilibrium set by the felt temperature, with a time constant of about 4.5 h.

Cold raises energy expenditure below 10 °C felt; heat raises thirst above 27 °C, and illness multiplies it further.

3.4 Expenditure and recovery

Each tile walked costs an extra 2.5 kcal, 0.06 water point and 0.06 rest point. A lit torch lasts 3 h and a fat lamp 6 h; they light up to 8 tiles at night and add 3 °C felt.

3.5 Health, illness, death

Health drops every hour a cause is active (damage adds up). It recovers when the body is well looked after. The figures below are measured on the needs update function.

Predators deal a one-off blow (see chapter 4). The cause of death recorded is the one causing the most damage at the time.

Sleep deprivation

Awake, rest drops by 2.1 points per hour: it falls to about 66 after a 16 h day and to 0 around 48 h. At 0 the body gives out where it stands: the character collapses and sleeps for 2.5 h and cannot be woken. This forced sleep restores only partial rest (cap 30, then 26, 22… never below 12) and adds a sleep debt. Each collapse, after more than 48 h of accumulated wakefulness, can be fatal: 7% risk at 3 days, 30% at 5 days, 50% at 7 days, 85% at 10 days, certain death around 11 days (cause: exhaustion). Three warnings are given at 1, 2 and 3 days without sleep. Sleeping voluntarily reduces the accumulated wakefulness; 7 h of continuous sleep (or rest of at least 95) clears the debt and the risks. The fatigue gauge then reads “sleep-deprived” with the number of days.

A death message gives the cause, the day and the biome. The player can then be reborn elsewhere in the same world (full needs, empty inventory apart from the provisions) or continue in God mode.

3.6 Slowdown and vision

Slowdown multiplies the duration of a step (1 = normal). It adds up for each impairment. Vision is the factor applied to the sight radius.

3.7 Fog of war and light

In Survival, the character sees tiles in their line of sight, within a radius that depends on light: radius = (3.5 + (12 − 3.5) × light) × vision factor, capped at 25 tiles. Vegetation and rocks partly block the view (a rainforest tree blocks half the radius, a boulder three quarters, tall grass almost nothing). A torch guarantees a radius of 8 tiles at night; a fire lights a radius of 2 + 6 × intensity tiles.

Tiles already seen stay visible as a remembered map; creatures and buildings are only shown in the current field of view. Exploration memory is kept per world tile and saved with the game.

3.8 Fire

A fire burns 0.55 kg of wood per hour and holds at most 6 kg. Intensity decreases with fuel and rain weakens it; without wood it turns to embers, then ashes. Near a lit fire, the character can cook, tend the fire, and light a torch or lamp.

3.9 Skills

Five skills range from 0 to 1: gathering, hunting, fishing, crafting, fire. They improve with practice: level += amount × (1 − level), with 0.02 by default; each action sets its own amount. They affect success chances: base + level × 0.4, clamped between 0.05 and 0.97.

3.10 Water: sources and risks

There are three water qualities. Freshwater (rivers, freshwater lakes) is safe. Stagnant water (ponds, marshes, mud, puddles up to 12 h after rain) quenches thirst but can make you ill: the risk depends on temperature and biome. Seawater and salt-lake water are harmful.

A water filter divides the risk; boiling the water in a pot near a fire removes it. Dew is collected at local dawn (between 5 and 8 am), except below 0.5 °C or where annual precipitation is under 250 mm:

4.1 Action table

The keys are those of the action bar; a key only triggers the action if it is available. The bar menus open with Alt + letter.

4.2 Gathering

Success chance is base 0.75 + skill × 0.4, multiplied by the seasonal factor (at least 0.35), capped at 0.97. The quantity depends on the biomass taken from the world tile. It ranges from 2 to 12 units.

4.3 Hunting

The character strikes with their best weapon. Hit chance: 50% + skill × 0.35 + 0.1 if armed + 0.1 for the bow and the spear, capped at 95%. Damage (fraction of the animal’s health) = weapon damage × (0.7 + skill × 0.5) × roll (0.6 to 1.4) × size factor, where size factor = 35 / mass^0.8, between 0.06 and 4. A bow shot consumes one arrow.

Counterattack: after a blow, a carnivorous or omnivorous animal, or one heavier than 120 kg, strikes back with probability 30% (45% above 120 kg). The impact power is min(0.5, mass / 500) × (0.5 to 1.5), converted into health loss: max(2, power × 85) points. A killed prey is added to the studied species (its traits become known).

4.4 Fishing

Catch chance = 0.18 + skill × 0.4 + gear bonus, capped at 0.97. Catch: ⌊carcass kg / 0.4⌉ × gear yield, at least 1 and at most 6. Only the best gear in the inventory counts, in the order of the table.

4.5 Butchering

Each action takes up to 10 kg from the carcass. Meat = kg × 0.85 × efficiency / weight of one unit of raw meat. Efficiency: 0.55 without a blade, 1 with a blade (chipped pebble, flint, stake, axe, scraper), 1.25 with a flint knife. Other products accumulate in fractions: one unit each time the total reaches 1.

4.6 Fire and cooking

The probability is multiplied by 0.3 in the rain outside a shelter, then increased by fire skill × 0.25, capped at 95%. A success consumes 3 branches (and 1 fibre if you have no flint); a failure consumes 1 fibre. A new fire holds 2.4 kg of wood; it burns 0.55 kg per hour, and at most 6 kg can be stored.

4.7 Meals

Eating consumes units of the best food (calories weighted by safety) as long as energy plus half a portion stays below 2500 kcal, up to 12 units. Each unit also provides water: 6 points for berries and fruit, 3 for mushrooms, 1 for the rest. For each unit, a roll against its illness probability (tab. 5.1); a single failure makes the character ill for 8 to 18 hours.

4.8 Taming

A wild mammal of 40 kg or less, herbivore, omnivore or small carnivore, that does not already have an owner, can be approached with food. Each offering consumes one unit of food (the first in the inventory); the animal stays wary until it has received 3. It must remain on an adjacent tile throughout the action. At offering 3, it follows the character and the “tame” objective is counted. The menu shows progress (“1/3 offerings”).

        ┌──────── target: 8 neighbours + aimed tile ──────┐
        │  ?  ?  ?                                        │
        │  ?  @  ?     → available actions                │
        │  ?  ?  ?       appear in the bar                │
        └──────────────────────────────────────────────────┘
   [Water][Gather][Eat][Fire][Hunt][Build][Rest]  [Inventory]

5.1 Item catalogue

The tables below list every item in the game with its values. “Illness” is the probability of falling ill when eating one unit. “Damage” is the fraction of an animal’s health removed per blow, before modifiers (tab. 4.3). A garment only counts if it is the best of its slot.

5.2 Recipes

Crafting consumes the ingredients and takes the number of ticks shown. The tool must be in the inventory but is not consumed. If the recipe requires a fire, a lit fire must be within 2 tiles (intensity above 0.2). Success is 70% + crafting skill × 30%, capped at 97%; a failure destroys 1 branch and 1 fibre among the ingredients. In Survival mode, a recipe must first be unlocked (chapter 7).

6.1 How it works

Placing a blueprint: open the Build menu (O key), pick a blueprint, and a placement bar appears with a ghost of the blueprint (green tiles: free, red: rejected; the bar gives the reason). The ghost follows the mouse: a click on the map or Enter places the site, R rotates the blueprint (Shift + R the other way), Esc cancels. There is no “Place” button: the pointer must not leave the map.

The blueprint requires every tile of its footprint to be free, the character to be within 14 tiles of the anchor point (in Survival), nobody to be standing on a tile, and the mean annual temperature to be within the blueprint’s limits. The blueprint rotates by quarter turns. Each non-free tile is built separately: you bring its materials (“Deposit”, or automatically when building), then build it (“Build tile”, taking the tile type’s duration). Deposited materials stay with the tile.

  SITE PLACED       MATERIALS             TILE            BLUEPRINT DONE
  ┌───┐            delivered tile by tile  built
  │ . │ site ──►  deposit or build ──►  ✓ ──► all tiles ✓
  └───┘                                        ↓
                                   interior shelter active

Impassable tiles (walls, fences, fixtures) block the character, animals and humans as soon as they are finished. A finished chest or storage pit keeps items the player puts in it.

Rejected locations: off the map, on water, on lava, on bare rock, on a tree or a boulder, on an existing construction or fire.

6.2 Shelter

The shelter felt on a tile (0 to 1) comes from two sources: (a) finished walls and fences give their “Adjacent shelter” value to the eight tiles around them; (b) once the blueprint is finished, each floor, hearth or bed tile takes the blueprint’s “Interior shelter” value, and a door 60% of it. The highest value wins. It affects the felt temperature (tab. 3.3), rain (none under full shelter) and sleep quality.

6.4 Blueprint catalogue

Each card shows the layout as drawn in the game (top of the blueprint first), the tile legend, the total cost and the conditions. The layout shown is rotation 0.

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7.1 Counters and conditions

The game keeps counters, fed only in Survival: fires lit (fires_lit), meals, drinks, animals killed, carcasses butchered, fish caught, food cooked, food preserved, nights survived, tiles travelled, items obtained (got:item), items crafted (crafted:item) and constructions finished (built:blueprint). A condition compares a counter with a threshold. A node or objective is gained when all its conditions hold. Skills can also be used as conditions.

7.2 Eras

In all, the graph has 144 nodes and 62 objectives. Some objectives and nodes of the late eras depend on systems that are not fed yet (sowing, herding, mining, trade…): they appear in the graph but cannot be obtained for now, and they do not break the chain of objectives.

7.3 Objectives

In the game, each objective is shown as a checklist of steps, one per condition (the “Objective” box under the gauges, and the Objectives window with Shift + B). The table below gives the same conditions and what the objective unlocks.

7.4 Unlock nodes

Nodes currently unavailable (56): Digging stick, Flint sickle, Hoe, Bread, Mud brick, Plough, Cheese, Hammered copper, Planks, Copper axe, Copper dagger, Wheel, Cart, Cloth, Beer, Bronze, Bronze axe, Sword, Bronze sickle, Cauldron, Sail, Iron, Steel, Iron plough, Lime, Mortar, Tiles, Pit trap, Field, Stilt house, Ditch, Ford, Foundry, Weaving workshop, Warehouse, Gravel road, Wooden bridge, Forge, Watchtower, Chief's house, Paved road, Iron forge, Stone wall, City gate, Stone bridge, Market hall, Reap, Dig a mine, Trade, Sail, Forge, Agriculture, Copper metallurgy, Bronzeworking, Ironworking, Masonry.

7.5 Unlock tree

The tree below is built from the conditions. Key: [O] objective, [R] recipe, [C] construction, [A] action, [S] knowledge. A node sits under its first prerequisite; the others are listed after “also”. Conditions in brackets are not nodes (counters, items to obtain).

══ EARLY PALEOLITHIC ══
[R] Chipped pebble
└─ [O] A first tool
   ├─ [R] Spear
   │  └─ [O] Hunt and butcher  (butcher)
   │     ├─ [R] Hide bag
   │     ├─ [R] Empty waterskin
   │     ├─ [R] Hide clothing
   │     │  └─ [O] Get dressed
   │     │     ├─ [R] Bone needle
   │     │     │  ├─ [R] Sewn clothing
   │     │     │  │  ├─ [R] Fur coat  (find: furs)
   │     │     │  │  ├─ [R] Fur hat  (find: furs)
   │     │     │  │  └─ [O] Sewn clothing  (also: Boots)
   │     │     │  ├─ [R] Boots
   │     │     │  └─ [S] Sewing
   │     │     └─ [C] Hide tent
   │     ├─ [R] Leather
   │     └─ [R] Dried meat
   ├─ [R] Axe
   │  └─ [A] Fell a tree
   ├─ [R] Flint knife
   ├─ [R] Scraper
   │  ├─ [A] Strip bark and gather resin
   │  └─ [O] Bone and flint tools  (also: Awl, Bone needle)
   │     ├─ [R] Javelin
   │     ├─ [R] Spear-thrower
   │     ├─ [R] Harpoon
   │     ├─ [R] Fish hook
   │     │  └─ [R] Fishing line
   │     ├─ [R] Bow drill
   │     └─ [R] Bow  (find: sinew)
   │        ├─ [R] Arrows
   │        │  └─ [R] Fletched arrows  (find: feathers)
   │        └─ [O] The bow and arrows  (also: Arrows)
   │           └─ [C] Bone hut  (find: bone ×8)
   └─ [R] Awl
      └─ [R] Bone whistle
[C] Windbreak
[C] Branch shelter
└─ [O] Build a shelter
   └─ [R] Rope
      ├─ [R] Woven basket
      │  └─ [R] Carrying basket
      └─ [O] Ropes and baskets  (also: Woven basket, Fishing net)
         └─ [C] Hut
            ├─ [C] Path
            ├─ [C] Smokehouse  (preserve food (2))
            │  └─ [O] The smokehouse  (preserve food (4))
            ├─ [C] Seasonal camp  (survive nights (30))
            ├─ [O] Build a hut
            ├─ [C] Palisade
            │  ├─ [C] Ditch  — unavailable
            │  ├─ [C] Palisade gate
            │  ├─ [O] The palisade  (also: Palisade gate)
            │  └─ [C] Watchtower  — unavailable
            │     └─ [O] The watchtower  — unavailable
            ├─ [C] Common hall
            │  ├─ [O] The common hall
            │  └─ [C] Chief's house  (inhabitants (40); also: Forge)  — unavailable
            │     └─ [O] The chief's house  (inhabitants (40))  — unavailable
            ├─ [C] Well
            │  └─ [O] A well
            ├─ [C] Dry-stone house  (find: stones ×40)
            └─ [O] Found a village  (survive nights (10))
[C] Built hearth  (light fires (3))
[A] Pick up shells
[A] Gather dew
[A] Drink stagnant water
[A] Medicinal herbs
[A] Cook
[S] Fire mastery  (light fires)
[S] Hunting  (kill animals)
[O] Light a fire  (light fires)
└─ [R] Torch
[O] Feed yourself  (eat (2); drink)
[O] Cook and preserve  (cook; preserve food)
├─ [R] Smoked meat
├─ [R] Dried fish
├─ [C] Drying rack
└─ [C] Storage pit

══ UPPER PALEOLITHIC ══
[R] Fat lamp  (find: fat)
[R] Flint-and-pyrite striker  (find: pyrite)
[R] Dye  (find: ochre)
[R] Shell necklace  (find: shells ×3)
[C] Pit trap  (kill animals (3))  — unavailable
[O] Angler  (fish (3))
├─ [R] Fishing net
│  └─ [R] Fish trap
└─ [A] Tame

══ MESOLITHIC ══
[R] Bark container  (find: bark)
[R] Grindstone  (find: seeds ×10)
├─ [R] Flour
│  ├─ [R] Flatbread
│  │  └─ [O] First flatbread
│  └─ [R] Bread  (also: Oven)  — unavailable
│     └─ [O] Bread  — unavailable
├─ [O] Seeds and flour  (find: seeds ×12; also: Flour)
│  └─ [A] Sowing  (find: seeds ×10)
│     └─ [R] Digging stick  — unavailable
└─ [R] Polished axe  (also: Axe)
   └─ [O] Polished stone
[O] Getting through winter  (last winters)
[O] The dog  (tame)

══ NEOLITHIC ══
[R] Clay pot  (find: clay ×3; light fires (3))
├─ [R] Jar
├─ [R] Porridge  (also: Flour)
├─ [R] Water filter  (also: Charcoal)
├─ [C] Wattle-and-daub house
│  ├─ [C] Longhouse
│  ├─ [C] Stilt house  (find: roseaux ×20)  — unavailable
│  ├─ [O] Wattle-and-daub house
│  └─ [O] A real village  (inhabitants (12); also: Raised granary, Well, Common hall, Palisade)  — unavailable
├─ [A] Boil water
├─ [A] Brew herbal tea
├─ [S] Pottery
├─ [R] Mud brick  (find: clay ×15)  — unavailable
├─ [C] Potter's kiln
│  └─ [O] The potter's kiln  (also: Clay pot)
├─ [C] Oven  (also: Flour)
│  └─ [R] Lime  (find: calcaire ×3)  — unavailable
│     └─ [R] Mortar  — unavailable
│        ├─ [C] Stone wall  (also: Iron)  — unavailable
│        │  ├─ [C] City gate  — unavailable
│        │  │  └─ [O] The gate  — unavailable
│        │  ├─ [C] Market hall  (inhabitants (100))  — unavailable
│        │  │  └─ [O] The market hall  (inhabitants (100))  — unavailable
│        │  ├─ [S] Masonry  — unavailable
│        │  ├─ [O] The wall  — unavailable
│        │  └─ [O] A city  (lay road tiles (100); villages (3); also: Market hall)  — unavailable
│        ├─ [C] Stone bridge  (also: Wooden bridge)  — unavailable
│        │  └─ [O] The stone bridge  — unavailable
│        └─ [O] Lime  — unavailable
├─ [C] Mud-brick house  (find: clay ×30)
├─ [O] Pottery
│  └─ [C] Pen
│     └─ [O] Livestock  (tame)
├─ [R] Beer  (find: grain ×10)  — unavailable
└─ [R] Tiles  (also: Potter's kiln)  — unavailable
[R] Flint sickle  (harvest)  — unavailable
└─ [O] The first harvest  (harvest (5))  — unavailable
[R] Hoe  (sow (10))  — unavailable
└─ [R] Plough  (tame)  — unavailable
[R] Cheese  (milked (3); find: sel)  — unavailable
[C] Field  (sow (3))  — unavailable
[C] Ford  (lay road tiles (5))  — unavailable
[A] Reap  (sow)  — unavailable
[A] Milk  (tame)
[S] Agriculture  (harvest (5))  — unavailable
[S] Herding  (tame)
[O] Seeds  (find: seeds ×20)
└─ [C] Raised granary
   ├─ [O] A granary
   └─ [C] Warehouse  (also: Planks)  — unavailable
      ├─ [A] Trade  — unavailable
      └─ [O] The warehouse  — unavailable
[O] Sowing  (sow (3))  — unavailable
[O] Paths  (lay road tiles (10))  — unavailable

══ CHALCOLITHIC ══
[R] Hammered copper  (find: cuivre_natif)  — unavailable
├─ [A] Dig a mine  (also: Hoe)  — unavailable
└─ [O] A green stone  (find: cuivre_natif)  — unavailable
[R] Charcoal  (light fires (20))
├─ [C] Foundry  (mine (5))  — unavailable
│  ├─ [O] Smelting  (smelt)  — unavailable
│  └─ [R] Bronze  (find: etain ×2)  — unavailable
│     ├─ [R] Bronze axe  (also: Forge)  — unavailable
│     ├─ [R] Bronze sickle  (also: Forge)  — unavailable
│     ├─ [R] Cauldron  — unavailable
│     ├─ [C] Forge  — unavailable
│     │  ├─ [A] Forge  — unavailable
│     │  └─ [O] The forge  (also: Bronze axe)  — unavailable
│     ├─ [S] Bronzeworking  — unavailable
│     └─ [O] Bronze  — unavailable
├─ [O] Charcoal
└─ [C] Iron forge  (find: minerai_fer ×3)  — unavailable
   ├─ [R] Iron  (find: minerai_fer ×5)  — unavailable
   │  ├─ [R] Steel  (forge skill 30%)  — unavailable
   │  │  └─ [O] Steel  — unavailable
   │  ├─ [R] Iron plough  (also: Plough)  — unavailable
   │  │  └─ [O] The iron plough  — unavailable
   │  └─ [S] Ironworking  — unavailable
   └─ [O] The bloomery  (also: Iron)  — unavailable
[R] Copper axe  (smelt)  — unavailable
└─ [R] Planks  — unavailable
   ├─ [R] Wheel  — unavailable
   │  └─ [R] Cart  (tame)  — unavailable
   │     ├─ [C] Gravel road  (lay road tiles (10))  — unavailable
   │     │  ├─ [O] The road  (lay road tiles (20))  — unavailable
   │     │  └─ [C] Paved road  (also: Bronze axe)  — unavailable
   │     │     └─ [O] The paved road  (lay road tiles (50))  — unavailable
   │     └─ [O] Wheel and cart  — unavailable
   ├─ [C] Weaving workshop  (find: laine ×5)  — unavailable
   │  ├─ [R] Cloth  — unavailable
   │  │  └─ [R] Sail  (craft: pirogue)  — unavailable
   │  │     ├─ [A] Sail  — unavailable
   │  │     └─ [O] The sail  — unavailable
   │  └─ [O] The loom  (also: Cloth)  — unavailable
   ├─ [C] Wooden bridge  (also: Ford)  — unavailable
   └─ [O] Planks  — unavailable
[R] Copper dagger  (smelt)  — unavailable
[S] Copper metallurgy  (smelt)  — unavailable
[O] The mine  (mine (5))  — unavailable
[O] The bridge  (bridge_tiles (2))  — unavailable
[O] Trade  (trade)  — unavailable

══ BRONZE AGE ══
[R] Sword  (forge (3))  — unavailable
[O] Tin  (find: etain ×2)

══ IRON AGE ══
[O] The red ore  (find: minerai_fer ×10)

8.1 Classes and diets

An animal is shown by the letter of its class, upper case for a large species, lower case otherwise. The colour indicates its diet.

A carcass is drawn in grey (#a8a8a8). Herbivores feed on plants according to their type; carnivores hunt; omnivores do both; scavengers feed on carcasses; insectivores eat insects (20 kg per tile at full density); piscivores fish.

8.2 Species traits

Each world holds at most 64 species at a time. A species appears with a founding population of at least 36 individuals, split into colonies. The total number of living animals is capped at 20,000. New species can branch off an existing one (a “parent” kinship link); a species with no individuals left is extinct.

8.3 Behaviour

At every step each animal picks an action based on its needs (hunger, thirst, energy, fear, temperature), its diet, its activity pattern and what it perceives.

Needs range from 0 to 1 (hunger, thirst, fear), and energy from 0 to 1 as well (0 = exhausted). Health runs from 0 (dead) to 1; thermal comfort from −1 (too cold) to +1 (too hot). Each animal keeps the last ten notable events of its life, shown on its sheet.

8.4 Plant food

Plants grow along a logistic curve, modulated by temperature, water and season; frost makes them wither. The maximum biomass of a world tile is the biome capacity (tab. 1.3) times the mass below, multiplied by 4: a 111 km tile has to feed a group, not a single animal. Insects form a separate population, 20 kg per tile at full density.

8.5 Seasonal migration

Migratory species remember the best areas for each season (Hiver, Printemps, Été, Automne). The world map is divided into blocks of 4 × 4 tiles. Every day, 60 individuals per species sample the quality of their location (food, weighted by satiety), which updates the memory, with slow forgetting. A group re-evaluates its location about every 3 days (1 to 1.66 times that delay) and decides to leave if local quality drops below 0.45. 12 days before a season ends, animals anticipate the next one. Journeys are made block by block, preferring corridors already used; migrants reinforce these corridors, which slowly fade (updated every 10 days). Herds follow their leader’s decision.

Around the character and the camps, local wildlife follows the real herds: when they pass, groups cross the area in their direction of travel, and in the off season migratory species become scarce there or vanish altogether.

   winter          spring           summer         autumn
  ┌────┐   ──►   ┌────┐   ──►   ┌────┐   ──►   ┌────┐
  │ ░░ │         │ ▒▒ │         │ ▓▓ │         │ ▒▒ │   remembered quality
  └────┘         └────┘         └────┘         └────┘   per block and season
        ╲_____ corridors reinforced by migrants _____╱

8.6 Climate events

The log keeps at most 300 recent events. A year has 360 days.

9.1 Individuals

A human has an age (Infant, Child, Adult, Elder), a sex, family ties (mother, father, partner, children), four individual physical traits (strength, speed, cold resistance, perception), needs, and a skill for each job (0 to 100). Their energy reserve is 30,000 kcal for a well-fed adult; hunger is 1 − reserve / 30,000. The needs are: hunger, thirst, warmth, fatigue, health, morale, fear.

Tribe lifestyle: Nomadic band → Seasonal camp → Semi-sedentary hamlet → Farming village. Mobility: Nomads → Semi-nomads → Settled. At first bands are nomads: every few weeks they break camp and follow the game. Little by little they settle; once the village is built they stay, except for families who bud off far away, or when the land no longer feeds them: some leave, or the whole village moves and leaves ruins behind. A band knows its surroundings well, the neighbouring land vaguely, and discovers the rest on the way.

9.2 Actions

9.3 Jobs

Jobs are assigned according to the group’s needs, the minimum age, the strength required, skills and the tribe’s discoveries. A skill improves with practice and is lost if the corresponding knowledge is no longer practised.

9.4 Resources

Resources are counted in kilograms (bulk goods) or in units (objects). Spoilage is the fraction lost per day at 20 °C, increased by heat; sickness is the risk per kg eaten.

9.5 Storage

Every unit of a resource is either in a store or in an open-air pile at the camp. Piles spoil 1.6 times faster and attract rodents and thieves (a loss of 0.4% per day for grain). Humans carry a limited load and take goods to the nearest suitable store; aggregated tribes simply distribute quantities.

9.6 Buildings

Building consumes materials and work hours (person-hours), and requires the building’s discoveries to be known and the climate to be suitable. Warmth is a gain in °C indoors; protection (0 to 1) works against rain and wind; capacity is the number of sleepers sheltered. Wear is a loss of condition per day (0.2% by default) as long as no repair is made.

Tribes erect their buildings on building sites at the camp: builders bring the materials and supply the work hours. If a material nobody can obtain (hide, sinew, bone without game) is missing for 24 stalled work-hours, the site waives it and carries on. A nomadic tribe moves its camp; a settled tribe founds a village.

9.7 Discoveries

Once per game day, each tribe rolls the probability of every discovery whose prerequisites it knows. This probability depends on context: tribe size, practice of the related jobs (hours per day), highest skill, climate, local resources (flint, clay, water, coast, fish, seeds, nuts, big game), cold or hunger stress, predator attacks, fires going out, years spent at the same camp… A global pace slows each era down.

Starting knowledge: Keeping fire, Knapped stone, Wooden spear, Hides. A discovery tied to a job can be forgotten if that job stops being practised.

9.9 Farming

A tribe that knows fields cultivates plots. Each field goes through the stages: Ready to sow, Growing, Ripe, Stubble, Fallow. Crops (cereal, legume, tuber) are derived from the world’s wild plants; rotation alternates cereal and legume. Each crop gains yield through selection, from 0.45 to 1.6. A harvest sets aside 60 kg of seed per full field.

Each achievement reads the progression counters (chapter 7) and a few extra counters kept by the game: biomes crossed, species observed, large animals killed, tribe encounters, day of the last encounter, nights spent below −10 °C, stagnant water drunk without falling ill, causes of death. When the condition is a threshold, a progress bar is shown in the game.