WikiBreeding & genetics
Breeds & body genes
The twelve breeds, breed %, named crosses, size, the speed gene, big heart and iron legs.
Every horse is a mix of twelve breeds, written as breed percentages that add up to 100. A foal’s breed is the exact average of its parents’. Breeds shape a horse: its stat profile, its best trip, its size and the genes it tends to carry. No breed is better overall; each is good at something else.
The twelve breeds
Each breed has a typical stat profile (the mean of its stat genes), a favourite trip, a liking for turf or dirt, a size and its own signature genes. The numbers below come straight from the game’s breed table.
| Breed | Spd | Sta | Bur | Dur | Ada | Tem | Total | Trip | Turf | Size | Signature genes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Thoroughbred | 450 | 430 | 430 | 420 | 410 | 410 | 2550 | mile | 70% | +3% | big heart |
| Arabian | 400 | 500 | 380 | 470 | 430 | 400 | 2580 | staying | 45% | −5% | big heart, dished face |
| Quarter Horse | 480 | 330 | 500 | 440 | 400 | 470 | 2620 | sprint | 20% | −2% | champagne, splash |
| Akhal-Teke | 440 | 480 | 400 | 430 | 470 | 360 | 2580 | middle | 45% | +2% | big heart |
| Standardbred | 430 | 470 | 380 | 470 | 400 | 450 | 2600 | mile | 25% | 0% | none |
| Appaloosa | 430 | 420 | 430 | 450 | 460 | 410 | 2600 | mile | 45% | −1% | leopard complex, pattern-1 |
| Paint Horse | 470 | 340 | 490 | 440 | 410 | 450 | 2600 | sprint | 25% | −2% | champagne, tobiano, splash |
| Mustang | 410 | 480 | 400 | 500 | 480 | 330 | 2600 | middle | 40% | −6% | champagne, silver, tobiano, leopard complex |
| Andalusian | 420 | 420 | 470 | 430 | 420 | 440 | 2600 | mile | 75% | 0% | pearl |
| Friesian | 430 | 470 | 410 | 450 | 430 | 410 | 2600 | middle | 65% | +5% | feathering |
| Warmblood | 420 | 470 | 420 | 450 | 440 | 400 | 2600 | middle | 80% | +6% | feathering |
| Marwari | 400 | 470 | 410 | 470 | 470 | 380 | 2600 | middle | 30% | 0% | curled ears, dished face |
The portraits show the coat and markings. They don’t draw breed shapes, size or the new patterns yet; the horse page lists those by name (see Coats & markings).
Breed %: foals are the average
A foal’s breed is the exact average of its parents’, to a tenth of a percent. A horse is purebred when one breed is 87.5% or more (the breed registries’ seven-eighths rule). Some two-breed crosses have their own names: both breeds need 25% or more and together 87.5%. Any other mix is a crossbred, named by its two biggest breeds.
| Pairing | Foal's breed | Label |
|---|---|---|
| Thoroughbred × Arabian | 50% Thoroughbred · 50% Arabian | Anglo-Arab |
| That foal × Thoroughbred | 75% Thoroughbred · 25% Arabian | Anglo-Arab |
| That foal × Thoroughbred | 87.5% Thoroughbred · 12.5% Arabian | Purebred Thoroughbred |
| Warmblood × Friesian | 50% Friesian · 50% Warmblood | Crossbred (Friesian × Warmblood) |
- Anglo-Arab: Thoroughbred and Arabian.
- Appendix Quarter Horse: Quarter Horse and Thoroughbred.
- Hispano-Arabe: Andalusian and Arabian.
Size: shape, not strength
Size is measured against an average Thoroughbred. It is the breed’s size plus a polygenic height gene (up to ±3%) plus +3% for each copy of the Height gene (Ht), which is incompletely dominant: one copy makes a horse taller, two copies taller still. Size runs from −12% to +12%. The Warmblood is the biggest breed (+6%), the Mustang the smallest (−6%).
A taller horse gains top speed and stamina and loses burst and durability; a smaller one the reverse. The points only move between stats, so the total never changes. Per whole 1% of size: speed +2, stamina +1, burst −2, durability −1.
| Size | Speed | Stamina | Burst | Durability | Total |
|---|---|---|---|---|---|
| −12% | −24 | −12 | +24 | +12 | 0 |
| −9% | −18 | −9 | +18 | +9 | 0 |
| −6% | −12 | −6 | +12 | +6 | 0 |
| −3% | −6 | −3 | +6 | +3 | 0 |
| 0% | 0 | 0 | 0 | 0 | 0 |
| +3% | +6 | +3 | −6 | −3 | 0 |
| +6% | +12 | +6 | −12 | −6 | 0 |
| +9% | +18 | +9 | −18 | −9 | 0 |
| +12% | +24 | +12 | −24 | −12 | 0 |
The speed gene (MSTN)
MSTN has two versions, C (sprint) and T (stay), and neither dominates. C/C horses are sprinters: their best trip is 200 m shorter than their distance genes say, with burst +15 and stamina −15. T/T horses are stayers: 200 m longer, stamina +15 and burst −15. C/T horses are milers with no shift. Like size, it moves points and never adds any.
| Breed | C copies | Sprinter (C/C) | Stayer (T/T) |
|---|---|---|---|
| Thoroughbred | 45% | 20% | 30% |
| Arabian | 15% | 2% | 72% |
| Quarter Horse | 80% | 64% | 4% |
| Akhal-Teke | 25% | 6% | 56% |
| Standardbred | 30% | 9% | 49% |
| Appaloosa | 45% | 20% | 30% |
| Paint Horse | 75% | 56% | 6% |
| Mustang | 30% | 9% | 49% |
| Andalusian | 35% | 12% | 42% |
| Friesian | 15% | 2% | 72% |
| Warmblood | 25% | 6% | 56% |
| Marwari | 25% | 6% | 56% |
Big heart and iron legs
- Big heart is recessive and rare: only a horse with two copies (bh/bh) has it, and then it gets +25 stamina potential. It is the one new gene that adds strength. Two carriers have a 25% chance of a big-heart foal. It stays unknown on the horse page until the horse races or has a Pedigree Scan.
- Iron legs is dominant: one copy multiplies the injury risk of every start by 0.80 (see Injuries & insurance). It is the sound-legged opposite of Fragile legs; a horse can carry both, and then both apply.
- Feathering (long hair on the lower legs) is recessive, curled ears dominant and the dished face incompletely dominant. These are looks only.
By the numbers live from the rules
- Breeds
- 12
- Purebred from
- 87.5%
- Height per Ht copy
- +3%
- Size range
- −12% to +12%
- MSTN trip shift
- 200 m
- Big heart
- +25 stamina
- Iron legs injury risk
- ×0.80
Horses from before the twelve breeds
Horses born before the twelve breeds arrived keep exactly the genes, looks and stats they had. They count as 0% of the eight new breeds, carry none of the new genes and are C/T milers, and their size never moves their stats. Their foals are ordinary new horses: they get their parents’ average breed and their own size. Breeding commitments made before the change foal the same horse they were always going to, plus the new genes. See Genetics & inheritance for how every gene is passed on.