Magical gene / spots and rings

Harlequin Shield

A saw-toothed shield across the flank, filled with lozenges that each have a smaller lozenge inside them - three tones, all hard-edged.

What it can come out as

Outcome	Carrying
Harlequin Shield	`Hqs/Hqs` · `Hqs/Hqc` · `Hqs/n`
Harlequin Shield, coloured	`Hqc/Hqc`
Wild type	`Hqc/n` · `n/n`

How each one is actually drawn - region by region, and the layers it is built from - is on the coding tab.

Crossing two of them

Finding one

About 1 in 1,786 wild horses is born showing this. That is the whole of the supply: catch one, or make one with the carrot below. Breeds set their own pools and a breed built around this gene will carry it far more often than the wild population does.

Wild pair	Shows as	How often
`Hqs/Hqs`	Harlequin Shield	0.002% — 1 in 50,000
`Hqs/Hqc`	Harlequin Shield	0.008% — 1 in 12,500
`Hqs/n`	Harlequin Shield	0.038% — 1 in 2,632
`Hqc/Hqc`	Harlequin Shield, coloured	0.008% — 1 in 12,500
`n/n`	Wild type	99.944%

Its gene carrot

The file

common/src/main/resources/horsegenetics/genes/harlequin_shield.json — a data-driven gene, not a Java class. It is listed in the index.json beside it and registered by Genes' class initialiser at startup.

Key	`horsegenetics.harlequin_shield`
Phase	magical — it adds signed colour in phase 3, after the pigment has resolved
Priority	317 — where it sits in the one `(priority, key)` paint order
Alleles	`Hqs` · `Hqc` · `n`
Varies per horse	8 values drawn once off the expressing allele copy, so a foal that inherits the copy inherits the look
Built from	SPOTS, TOWARD, WAVES

Why it is built this way

Imported from the magic-gene intake, 2026-09-08. Every layer starts from the SAME saw wave, so the lozenges are clipped to the shield and cannot wander off it. Drawn largest first - the reverse order paints the core and then covers it.

What it paints

Each outcome, described the way the gene file describes it, and then the layers that draw it in the order they are painted. The prose is the part a reader checks a bake against; the list underneath is what the engine actually did.

Harlequin Shield

Every layer starts from the same saw wave, so the lozenges are clipped to the shield and the shield keeps its teeth - a saw is the one waveform that gives a raked straight edge. The three tones are drawn largest first, which is the only order that leaves the core visible.

the toothed shield across the flank — WAVES, painted with TOWARD
lozenges set into it — WAVES × SPOTS, painted with TOWARD
and a smaller lozenge inside each — WAVES × SPOTS, painted with TOWARD

Harlequin Shield, coloured

The same shield with the two inner tones in colours the line carries. Fully recessive.

the toothed shield across the flank — WAVES, painted with TOWARD
lozenges set into it — WAVES × SPOTS, painted with TOWARD
and a smaller lozenge inside each — WAVES × SPOTS, painted with TOWARD

Wild type

No shield.

Paints nothing.