# Balance Lab

> Batch-simulate one specimen on the real game engine — sweep movement/feeding/eyespot tiers, the diet triangle and food richness, and measure intake, survival and travel in isolation.

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.. toc::

### Movement × intake, isolated

The arena couples everything — rivals, hunters, the NPC ecosystem, colony economics — which
makes it hard to tell whether a build starved because its **movement** couldn't reach food,
its **feeding part** couldn't take it, its **eyes** never saw it, or the dish was simply too
poor. This lab strips all of that away: one specimen, the **exact engine the game runs**
(`EVO.tick` — same movement archetypes, feeding cones, diet-class triangle and energy
economy), in a dish reshaped to **food only** at a chosen richness.

.. admonition::How to use it
    :color: blue

    **▶ Watch one run** renders the dish in slow motion so you can *see* a mechanic work
    (or not — a pseudopod at poor, say). **⚡ Run batch** executes N headless runs fast and
    reports per-run intake: prey eaten, dna banked, mean/min energy, survival or the
    starvation tick, distance covered and speed. Every batch's aggregate lands in the
    **session history**, so sweep one dial at a time (tier, diet, richness) and compare rows.

.. exec::docs.balance_lab.balance_lab

### Reading the numbers

- **survival %** — the headline: a balanced build at *medium* richness should mostly live.
- **prey μ / dna μ** — the intake rate. Herbivores bank dna from grazing (prey stays 0);
  carnivores need kills — exactly as in-game, the **feeding part picks the eating lane**
  (a jaw hunts even on a herbivore's body, a filter grazes).
- **energy μ / min** — how close the run skated to exhaustion; a low min with survival
  means the build lives tick-to-tick.
- **dist / u-per-tick** — what the movement tier actually buys; compare none → great with
  the same feed to separate "couldn't reach food" from "couldn't eat it".

Findings tuned here port straight into the game: the engine constants live in
`lib/evolution/config.py` (ENERGY, SPAWN, diet classes in `lib/diet.py`) and this lab reads
them live — change a constant, restart, re-run the same sweep.


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*Source: /balance-lab*