Magical gene / mane and tail

Guppy

The mane cut into hard vertical bands of two to four saturated colours, and the tail streaked lengthways in the same palette. The body is untouched.

What it can come out as

OutcomeCarrying
GuppyGup/Gup
Guppy carrierGup/n
Wild typen/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 1,250 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 pairShows asHow often
Gup/GupGuppy0.08% — 1 in 1,250
n/nWild type99.92%

Its gene carrot

The file

common/src/main/resources/horsegenetics/genes/guppy.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.

Keyhorsegenetics.guppy
Phasemagical — it adds signed colour in phase 3, after the pigment has resolved
Priority403 — where it sits in the one (priority, key) paint order
AllelesGup · n
Varies per horse3 values drawn once off the expressing allele copy, so a foal that inherits the copy inherits the look
Built fromAXIS, PALETTE, STROKES

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.

Guppy

Colour runs the full length of the crest, divided across it into discrete upright bands - three to seven of them, irregular in width, and hard-edged where they meet, with no blending anywhere. Some bands are the hair's own colour or white instead. The forelock follows the same rule at a smaller count. The tail is different: there the colour lies in long streaks running with the fall of the hair rather than across it, over the upper part of it, interleaving where two hues meet into a mottled flame rather than a clean stripe. Both use the same set of hues.

  1. upright bands across the mane — STROKES, painted with PALETTE
  2. lengthwise streaks down the upper tail — STROKES × AXIS, painted with PALETTE

Guppy carrier

One copy shows nothing whatever. Two carriers bred together are the only way the banding appears.

Paints nothing.

Wild type

Ordinary hair.

Paints nothing.