Skills: your body and your knackSK

SK1: bodies and the bench

Every sibling carries a body and what they've learned (PlayerBody, in Tech): muscle and fat, two independent axes (skinny, chubby, ripped, strongman), plus negotiation and lessons. The character as it looks today is the start: muscle 0.20, fat 0.30. Players see words and bars, never the numbers.

Getting stronger

Every gain shrinks as you get stronger: gain = rate × (1 − muscle). At most one session counts per day (the gym or the bench, the better one); hard work adds on top (SK2).

• Grandpa's bench and kettlebells (home): hold E on the bench, 20 game minutes, free, the bench's gain.
• The bench alone three times a week takes a new sibling from 0.20 to about 0.30 in six weeks (the gyms go further: SK2).

Fading

After 4 days with no session, muscle drops 0.004 a day, never below the start; a working day counts as half a session. Six weeks of gym is lost in close to three months of nothing, gently. Fading runs at night (EndDay), with the food reset (SK4).

• Difficulty: a new Mishaps row in Difficulty: muscle fades never (Relaxed), as written (Normal), ×1.5 faster (Hard). The feel itself has no row: presets never change the feel; your body does.

The skills screen

• The thing: grandpa's old weight bench and two kettlebells in grandma's garage, at the Workshop end: a new StationKind.Bench (a Blender model). E opens the screen, like the calendar opens the week; no text on the prop. Holding E on it trains.
• The screen, one per sibling, tabs for the others:
  • a front silhouette that matches your body (the same fat and muscle shapes as the character, SK3);
  • Strength as a bar and a word: Soft (below 0.30), Fit (0.30), Strong (0.50), Ripped (0.75 and up);
  • Shape as a bar and a word: Skinny (below 0.15), Lean (0.15), Comfy (0.40), Big (0.65 and up);
  • Negotiation as its word (Green to Shark, SK5) and what it lets you see;
  • Knowledge: the tiers you have and the lessons left for the next one (SK7);
  • today: what you ate, the boost, the last session, days until muscle starts fading;
  • the gym card: which gym, paid until (SK2).
• Hints in the world too: your own forearms on the handle in first person (SK3), sibling quips ("since when do you have arms?").
• Sandbox: F1 sliders for muscle, fat and negotiation per sibling.

Needs: SB1 · Done when: the tests pass (the BodyFeel floor, the gain and fade curves) and, on two instances, a guest trains on the bench and both players see the guest's bar change (mismatches = 0).

SK2: strength in the hands

The mower reads the body. Better only: today's tuned mower is what a new sibling feels; muscle only improves it (capped around +15-20%), and losing muscle brings it back toward today's feel, never below. Fat changes its character, never makes it weaker.

What muscle changes

s = how far above the start you are: (muscle − 0.20) ÷ 0.80. At s = 0 the mower is exactly today's.

Each multiplier scales with s; MowerController (push, turn, tip, heavy grass), carrying and the pull cord read them from BodyFeel. Gear does the same job: a self-propelled mower makes muscle matter less. Buying gear or building muscle is the player's choice.

What fat changes

f = how far above the start you are: max(0, fat − 0.30) ÷ 0.70.

• Momentum: the mower coasts more and takes longer to stop and turn (+30% coast at full f); you plough through heavy grass (+10% before it slows you, added to muscle's). Different, not weaker: push never drops below today's.
• On foot (no mower): up to 8% slower walking and a shorter hurry at full f. The only thing that gets worse.
• Below the start (thin): no feel change, just the look.

Work gains

Pushing in heavy grass and carrying bags add muscle at 0.003 per hour (the same shrinking gain), settled with the job.

The gyms

• Rough pace: FitZone three times a week takes a new sibling from 0.20 to about 0.50 in six weeks.
• A destination on the town map (like the store): pick it, ride there, one game hour passes with a short scene (a fade, a grunt, a quip), then back home or onward.
• The subscription is a monthly bill (ECONOMY's bills); without wallets yet the company pays, and it becomes a personal expense with EC2.
• Co-op: the group travels together (today's rule), so the host picks the gym; each sibling with a card trains, the others wait or pay a $10 day pass. Going alone comes with split co-op.

Needs: SK1 · Done when: in the sandbox, muscle 0 feels exactly like before (same numbers) and full muscle is clearly nicer.

SK3: bodies you can see

Feasible and cheap at runtime: shape keys (Unity blend shapes) on both rigs. The keys themselves are built by CH14 (bodies for the whole cast, in the MVP), with this recipe; SK3 makes a sibling's keys follow their muscle and fat.

• The recipe (characters.py, done in CH14): build the body as today, then again with bigger arms, chest and shoulders (Muscle), a belly, rounder arms and legs and a fuller neck (Fat), and a narrower torso and limbs (Thin). Same topology each time, so each difference becomes a shape key. Outfits are painted on the same mesh, so clothes follow. Hair, beard and the googly face stay; a "chubby cheeks" key is optional. importBlendShapes on, flat-shaded normals kept, prefabs rebuilt.
• Unity: CharacterLook.Apply sets the weights: Thin = (0.30 − fat) ÷ 0.30 below the start, Fat = f, Muscle = s. Remote siblings (NetAvatar) and the skills screen's silhouette use the same weights.
• First person: the player's own arms use the same mesh, so thicker forearms show on the handle.
• Checks: Push, PushIdle and the gestures at full Fat + full Muscle (arms into the belly); bend poses near the mower handle; the wardrobe's face zoom.

Needs: SK1, CH14 · Done when: the four corners (skinny, chubby, ripped, strongman) render cleanly in every pose.

SK4: food

Food is optional and shapes the body: no hunger bar. What you eat moves fat over days and gives short boosts; skipping meals never hurts (you just slowly lose a little fat).

• Burning it: −0.002 per hour of mowing or carrying, −0.005 per training session. Fat moves slowly: a working day (about 5 hours) burns 0.01, so pizza every night still adds about 0.005 a day; a month of it is visible, a season makes a big sibling. Cooked meals on working days slim you down.
• Buying it: food comes with the shopping (the grocery run arrives with ECONOMY's household costs); until then the fridge restocks itself and food is a weekly cost line.
• The client's cake: personalities that offer it do so at the door after the job; take it or not.
• What you ate today and the boost reset at night.

Needs: SK1 · Done when: in the sandbox, a month of pizza every night visibly rounds a working sibling, cooked meals on working days slim them and give the push boost until the next meal, skipping meals costs nothing, and a client whose cake you take is pleased.

SK5: negotiation

Learned on deals, used in the haggle. It gives information, not better odds: the money still comes from what you ask.

Learning

After a closed haggle (agreed or met halfway), gain = 0.05 × closeness × novelty × (1 − negotiation):

• closeness = the markup you got ÷ the client's ceiling (closer to their limit = more learned);
• novelty: the first deal with this client 1.0, then 0.5, 0.25, ... (no farming one neighbor);
• a refused ask teaches a little (0.01 × novelty): you learn where the line was.

Roughly, with new clients and fair asks: 7 deals to Decent, 15 to Good, 40 to Sharp; Shark is rare.

What you see

It hooks into today's +10% / +25% haggle buttons first, then into jobs J3 and J7's markup and ceiling as they land. Jobs: from the phone call to the review owns the haggle; this idea says what a skilled negotiator sees.

Needs: SK1, J3 · Done when: a new sibling reaches Decent after about 7 fair deals with new clients and sees the client's mood in calls from then on, each repeat deal with the same neighbor teaches less, and the level never drops.

SK6: client taste

Body shape works through client taste, not one charisma number: each client personality (Jobs: from the phone call to the review, the client page later) gets a taste.

Only the sibling at the door or on the call counts, so in co-op the right sibling answers. Never more than ±5%: taste is flavour, not a wall.

Needs: SK1, SK3 · Done when: a Feeder client gives the round sibling at the door better haggle odds than the lean one (5% at most), and in co-op only the sibling who answers counts.

SK7: knowledge, the bench in tiers

Taking a mower apart is know-how, so the workbench is gated by Knowledge, in tiers. Every task stays payable at the store's service desk (MO5b), so a locked task costs money, never progress: learning is how you stop paying the mechanic. Built with the 3D bench (MO11).

• Locked at the bench: the part doesn't come off; your sibling says "No idea how that comes apart" and the bench screen shows two ways out: Book it at the service desk (today's price) or Where could I learn this? (which manual pages and videos teach it). No text on the bench itself.
• Lessons (lessons, per sibling, never forgotten):
  • Harold's manual: his notes stay shared (one sibling finds a note, everyone can read it), but the lesson goes to whoever reads the page. His back pages cover the Mechanic tier (rope, belt, wheels: "The spring WILL bite you. — H."); the Engine tier has one page only (Harold "never trusted himself inside an engine").
  • Repair videos on the computer (a video site in the in-game OS): a Mechanic series (4 videos) and an Engine series (6), about 30-45 game minutes each, free (with ads, a joke). Siblings watching at the computer together all learn: a couch evening.
• Learned by reading and watching only: doing a task doesn't teach the next tier.
• Co-op: the sibling who learned does the job, another reason for roles to emerge. Locked tasks are per sibling: a sibling who knows can take the bench.

Needs: SK1, MO9, MO11 · Done when: a sibling without the Mechanic tier can't take the starter rope off and gets the two ways out; after reading Harold's back pages and watching the Mechanic videos they can, and a sibling who didn't still can't.