Zones

Zones are the territories one dish is divided into. Each is held by whichever side dominates it with biomass, and a zone walked out of goes neutral again. Every lab in the dish has one zone it calls home, and a lab loses the dish when an opponent holds its home zone for two unbroken minutes. Held ground feeds the cells standing on it and pays the lab that holds it, and no zone but a home zone decides the dish. Ground changes hands on a meter rather than at a moment, so a zone has to be won and not merely walked into.

The zone set

A dish with no authored zones is divided into seven: a core basin at the centre, and six ring zones one every 60 degrees. The first ring zone is aimed down the dish’s acid direction, so one lands on the acid pole and the opposite spoke near the cold pole. The seven reach the dish interior boundary exactly, so every point inside the dish belongs to a zone. A map that authors zones draws its own set instead, owns only the ground it drew, and leaves the rest belonging to nobody.

Every zone has one pH and one temperature, derived at the zone’s centre from the dish’s acid and cold poles. A zone pointing far enough toward a pole takes that pole’s flavour, acid or cold; the rest are neutral, and the centre zone is the basin.

Holding a zone

Control is recomputed from the live dish about twice a second, and it runs both ways, so ground is never banked by having once been taken.

The pass weighs biomass, not heads. A cell contributes its area, the square of its current radius, to the zone its centre sits in. A plasmodium also contributes at each of its network tips, in whichever zone the tip is, because one plasmodium is a single cell whose veins can span the dish. Contaminant cells score for the rival, and a disowned cell scores for neither side.

A side counts as present in a zone only above a hold floor of biomass. The floor scales with the zone’s share of the dish, so a large zone costs more to hold than a small one, and it never drops below a fixed minimum. The current holder, and whoever is part-way through taking the zone, are scored against 60% of that floor: taking a zone costs the full floor and keeping it costs less, so ordinary births and deaths cannot flip it.

• Neither side above its floor: the zone is neutral.
• One side above its floor: that side leads the zone outright.
• Both above: the holder keeps the lead until the challenger’s biomass reaches 1.5 times the holder’s.

That decides who is winning the zone. It does not change the holder, which only the capture meter does.

The capture meter

Each zone runs a meter that fills while one side holds a lead the zone’s current holder does not. The zone changes hands when the meter fills, and not before.

The meter drains at 0.6 of its fill rate when the lead is lost, so a wobble mid-push costs progress without erasing it. It resets to zero outright when a different side takes the lead, so two rivals trading the lead can never jointly evict a holder. A part-taken zone is not saved and does not survive leaving the dish.

Winning and losing a dish

Every lab in the dish has a home zone: the zone nearest where that lab’s cells landed, derived from the dish rather than authored, and resolved once per visit, so a dish re-entered later can resolve a different home zone than it did before. A lab is eliminated when an opponent holds its home zone for 120 unbroken seconds of dish time. The player loses the dish when a rival does that to the player’s home zone, and takes the dish when every rival in it is eliminated. Holding every other zone wins nothing, and winning a node dish conquers that node on the Bionet.

The countdown re-arms from full on any dip: taking the home zone back for a moment restarts the two minutes rather than shortening them. It runs on dish time, so a paused dish holds nothing, and it is not saved. Elimination is a latch, and taking the ground back afterwards does not put a lab back in the run. A rival that never put a cell in the dish cannot be eliminated, and a dish that resolves to no zones arms neither side. Nothing on the dish marks a home zone.

Winning is a phase and not an ending: the dish keeps running so the player can preserve what they want to carry out, and the end card fires when the player ends the run. The win stops strain repricing and the biomark dividend, while trophin keeps paying. A defeat returns the loadout and marks the run inactive, and the plate itself stays on disk.

What held ground pays

Held ground drips ordinary nutrient particles into itself, whichever side holds it. The particles have no owner, so a rival pushing into a zone eats what that ground makes while taking it. The drip scales with the zone’s area and with maturity: a freshly taken zone pays a fraction of full worth and climbs to full over unbroken hold by the same side, and losing the zone resets it to the floor.

Only a player-held zone pays the player.

Held ground also reprices the strains standing on it: a zone’s worth is credited to the player’s strains in proportion to their biomass share of that zone. Capturing a zone grants the next rung of the intervention-tool drip, and those tools are not taken back when the ground is lost.

Rival clades

A node dish entered fresh is seeded with two rival clades, one adapted to the acid pole and one to the cold, each placed inside the zone carrying its flavour and tuned to that zone’s own derived pH and temperature. Taking a pole zone therefore needs a strain that can live on it.

Their cells are ordinary contaminant cells, and they take and lose ground by the rules above. The seed is sized from the player’s own colony as it stands in the dish at seed time, multiplied by the node’s own factor and split across however many fronts the dish resolves; no clade carries a count of its own. Seeding happens once, on a fresh dish only, because a resumed plate already holds the rivals that survived the last session.

The cells are the deployment of the rival lab assigned to that node. A lab that has banked a lineage for a clade re-deploys that genome; a lab with an empty roster seeds the generated adaptation and founds its roster from the cells that just landed.