one dataset · paper, tables, graph, wiki
simgrammar the grammar of simulation

watch

1 short with this record on screen
Short 1: The five most common parts, opening frameplay · 0:38
rendered · short-01.mp4 · drawn from the dataset

short 1 0:38

The five most common parts

transcript

The five parts that turn up most often in simulation games don't simulate anything.

We broke 179 of them into their parts. First is the pause button, in 46 percent of them. Then placing buildings where you like, support for mods, a tech tree, and scenario goals.

Production chains come sixth, and they're the first part on the list that models something in the world: ore into plates, plates into gears.

The parts a game is known for are rare. RimWorld's storyteller, its mood breaks and its body-part injuries each show up in fewer than ten catalog games.

also on the pages for

definition

Owns, per creature, a tree of body parts with hit points, tissue layers, or functions, plus a list of conditions such as cuts, burns, fractures, bleeding, infection, scars, and missing or artificial parts. Damage lands on a sampled part; part health feeds capacities such as consciousness, moving, manipulation, sight, breathing, and blood pumping, which scale work speed, combat, and survival. Each tick bleeding drains blood, infections race against immunity, and tended wounds heal. RimWorld derives capacities from parts: consciousness below 30% keeps a pawn from waking, moving below 15% incapacitates, each arm supplies half of manipulation, blood pumping at 0% is fatal, poor tending raises infection and scarring risk, and each bionic leg adds 12.5% moving. Dwarf Fortress damages tissue layers per part; Project Zomboid tracks wounds per body region. Inputs are damage and treatment; outputs are capacity multipliers, pain, and death.

player experience

Injuries become specific stories: a colonist missing a hand works slower, a hunter with a shattered leg cannot flee. The player triages by which wound threatens life first, stops bleeding before worrying about infection, and plans around lasting disabilities or replaces parts with prosthetics.

design levers

  • granularity of the body tree: regions, organs, tissue layers
  • mapping from part damage to capacities and from capacities to actions
  • bleeding rate, infection chance, and healing rate, and how treatment quality modifies them
  • permanence: scars, lost parts, chronic pain
  • replacement options such as prosthetics, bionics, and transplants, and their availability

failure modes

  • Too many parts and conditions make the health screen unreadable, so players cannot tell what is lethal.
  • Fine-grained damage with high lethality makes outcomes feel like dice rolls, such as death from one hit to a vital organ.
  • Permanent disabilities without replacement paths make injured characters dead weight the player discards.

dynamics

  • Injured agents work slower, lowering output and raising pressure on healthy ones.
  • Demand for medicine, doctors, and prosthetics creates a medical economy.
  • Disabilities shape character identity and the stories players tell about them.

open questions

  • Can language models narrate injuries and recovery so deep body models stay legible without a dense health tab?

appears in

the paper, 3 sections · 5 episodes · 1 short
paper

4. A grammar of simulation games

linked in this section of the paper

paper
paper

5. The structure of the design space

linked in this section of the paper

paper
paper

6. Five ceilings

linked in this section of the paper

paper
glossary

Glossary of mechanics

listed under biology & health, with its summary

book
ep 1

Every simulation game is made of the same parts

on screen at 0:32 rimworld, in parts, 1:23 rare parts

episode
ep 2

Where the parts came from

on screen at 4:55 after 2000

episode
ep 3

Families across genres

on screen at 4:07 odd couples, 7:31 close

episode
ep 4

Why deep systems are hard to read

on screen at 5:51 choosing a point

episode
ep 5

The five ceilings

on screen at 5:18 minds made of formulas

episode
short 1

The five most common parts

0:38 · on screen in the short

short

sources

1
RimWorld Wiki contributors (2026). Health. RimWorld Wiki

provenance

runs in log/runs
2026-10-24
created2026-10-24-taxonomy-m5taxonomy