Derby Owners Club Breeding Planner

Model status: the foal-build routine is decoded byte-exact from the SH-4 code. Implemented exactly: internal average, soft clamp, hard cap 45, external floor-average, pedigree count (matched extremes), the 1-in-32 rare birth band, sex roll, the 32-bit LCG, and dirt: the game keeps the dirt rating as two halves and gives the foal the rounded-down average of each half separately (136 and 119 give 119, not 127); a parent with dirt 0 is given a random rating for each breeding, shown here as the middle of the possible results. Correction: earlier versions ranked "dirt aptitude" by a grade read from the catalog bytes at +48, which hold the coat, not dirt; the dirt column and objective now use the real 0 to 255 rating. Two more: these are World Edition Rev C's foal rules (DOC 2000 runs the same code); DOC '99's foal code is different (it has no rare band, and its pedigree bonus, +3 to all three internals at 4 or 5 matches and +6 at 6, is not modelled here), so the DOC '99 tab shows the parents' floor average capped at 45 and uses World Edition's dirt rule; Rev D adds a tamper check (if all three averages are above 61, which no genuine card can reach, the foal starts from 45, 43 and 40), so treat that tab as an estimate. Catalog horses never wear down, but at a World Edition cabinet a horse of yours from its 11th breeding on is used as a weakened copy (stats 2 to 5 lower, symbols 1 or 2 lower; its own card never changes), which this planner does not model. And each generation here breeds at its birth internals: in the game a foal starts from its parents' current internals, so racing parents up first can beat this projection (it helps until the pair averages 45 on a stat; 50 or more also gives 45; an average of 46 to 49 gives only 41 to 44).