Four cells, read line by line.

Nucleus capacity is the param times eight bytes, and a genome that will not fit in its nucleus is truncated at the next division. This genome is 342 bytes against the ancestor's 230. At the ancestor's param of 40 the nucleus holds 320 bytes — so every daughter would be cut off mid-file, losing the tail of the divide gene, and the lineage would divide once into something sterile and stop.

So the param goes to 56. That is not a workaround, it is the mechanism working: genome bloat costs a bigger nucleus, a bigger nucleus costs upkeep, and a lineage that grows its genome without earning the difference is outcompeted by one that did not. There is no rule against long genomes anywhere in the engine. There is just a bill.

Notice the chloroplast has gone the other way — 55, down from the ancestor's 60. The upkeep budget has to make room for the spike, so being a predator here means being a slightly worse plant. That trade is not encoded anywhere either; it is what happens when everything costs something out of one account.

BUILD puts a spike in slot 5, and then OSET sets its control input. OSET takes a value, which control input to write, and which slot — so this writes 16 to control 0 of slot 5, which is the spike's extension.

The 16 is computed rather than written, and that is a deliberate piece of genome craft: an immediate's template is only as long as the number needs, so a small IMM and a shift is shorter and more mutable than spelling the number out. A mutation to the shift count moves the extension by a factor of two; a mutation to the IMM moves it a little. The genome has two dials of different coarseness on the same number.

The number itself is the interesting part, and it started out at 512. A spike damages what it touches, and it has no idea what it is touching — the engine filters victims by “not me”, “occupied” and “within reach”, and that is the whole list. There is no kin check and there must not be one, because a special case for “my own offspring” is exactly the sort of flag that would stop this being emergence. A daughter is born inside her mother's reach, and this genome has no cilia, so neither of them can leave.

One founder in the primordial soup, 2,400 ticks, sweeping only the extension: 4 → 55 cells, 16 → 11, 32 → 3, 64 → 1, 128 → 1, 512 → 1. Everything else was ruled out by measurement rather than argument — not the divide guard, not the energy budget, not the copy loop, not the want of prey. It divides perfectly well. The daughters die.

Those numbers are much smaller than the ones this page used to carry, and the shape of the curve is the part that survived: every doubling of the extension costs most of what is left, and past sixty-four the lineage does not get a second generation at all. The engine's whole tempo was halved between the two measurements. Which is the argument for re-running a sweep rather than quoting one — the conclusion held and every figure in it moved.

So the finding this genome exists to carry is that an armed cell which cannot tell kin from prey, and cannot move away from either, has to carry a weapon its own children can survive. Sixteen is one point of damage a tick — a prey cell with a membrane of twenty-four takes about twenty-four ticks of unbroken contact to kill, which is a real weapon and a slow one. Half extension is not a weapon at all. It is a sterility switch.

Ten lines, and they are the whole difference between this genome and `hunter.mm`. A lysosome in slot 6, opened nearly all the way.

Carrion is chemical 15, and it is deliberately not flagged as structural — a cell cannot build a body out of it directly. It has to be digested into something usable first, and a lysosome is the only thing that does that. This is what makes scavenging a distinct trade rather than a free bonus for standing near a corpse, and it is why the spike alone is a bad deal.

It also means the predator does not need to kill in order to eat. A lysosome pays off next to anything that died, however it died. Predation and scavenging are the same organelle pointed at different opportunities, and the engine does not distinguish them because there is nothing to distinguish.

The vegetable's driver is four lines. This is eight, and the two that are new are the whole subject: dress puts the colours on, and watch decides every cycle whether the weapon should be out.

Note where watch sits — after the body is built and before the cell feeds. The decision is remade every time round the loop rather than latched, because the thing standing next to you changes and a cached answer would be wrong the moment it moved.

Three instructions, and this is the entire signalling mechanism. SETBADGE writes fifteen bits that anything touching this cell can read, that the engine does absolutely nothing with, and that cost nothing to wear and nothing to forge.

That last part is not a weakness. A badge that could not be forged would be an identity card issued by the physics, and the engine deciding what a family is would be exactly the special case that stops this being emergence. Another lineage is free to wear 210 without meaning it — which is the arms race, and it is supposed to be available.

The badge is also inherited, so a daughter is already wearing this before she has executed a single instruction. She has to be: the ticks in which a newborn is in danger are precisely the ticks before her first cycle has run. Setting it here as well costs two instructions and keeps the marker and the genome from drifting apart.

A founder is the exception, and it is worth knowing before you place two of them touching. She is seeded bare-faced and does not dress until her first cycle completes, so for a few ticks she is a stranger to her own kind.

A spike in slot 5 and a touch sensor in slot 7. The sensor is the only structural difference from the predator and it is not free — another organelle, drawing upkeep every tick, on a lineage that was already the most expensive thing in the library.

What it buys is the right to carry the spike at full extension, and that turns out to be worth far more than it costs. Notice that this gene does not set the extension at all. That decision belongs to the next one, because it is not a property of the body — it is a property of the moment.

Read what the nearest thing is wearing. Read what I am wearing. Compare. CMP leaves zero when they match, so JMPZ is “one of mine — put it away”.

Reading its own badge back rather than comparing against the literal in #dress is the detail that makes the lineage able to move. A mutation that changes the badge changes what this cell wears and what it answers to in the same stroke, so a lineage can drift its colours and still know its own children — and diverge from its cousins as it goes. Hard-coding the number here instead would make every such mutation an instant matricide.

The comment on the 24 is the sharpest illustration on this page of what the version stamp is for, and it is worth reading twice. The membrane's own scalars sit after its chemical readings, so every chemical added to the world shifts them along: that reading was 21 when this genome was written, 22 once inert dinitrogen landed, and 24 once calcium and carbonate did. The bytes did not change. What they mean did. An archived genome replayed under the wrong instruction set is not slightly wrong — it is reading its own oxygen level and calling it a badge.

The first test is the one that is easy to leave out and expensive to leave out. A cell touching nobody reads a badge of zero, which differs from its own — so without it a solitary cell arms permanently and is the predator again, paying the dearest upkeep in the catalogue to menace open water.

It asks the sensor how many things are in reach. It used to ask what the nearest one was wearing and treat a zero as an empty space, which looks equivalent and is not: somebody wearing nothing also reads zero, and that is every founder the world seeds and every genome in this library but two. So the guard against menacing open water was also a guard against attacking anything that had not chosen a badge, and this cell went through entire runs without ever drawing. Eight of these among eight ancestors over eight thousand ticks went from nought wounds and nought ticks with the spike out to a predator that draws on a stranger and sheathes for its own children. The sensor reading it needed had been there since the motility milestone; the genome was asking the wrong question of something that could already answer the right one.

And the 512 is the joke of the whole file: it is exactly the extension that sterilised the predator. The same number that made a weapon unusable makes this one formidable, because the difference was never the weapon.