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Derby Owners Club Breeding Planner

Community tool. Decoded foal-build model. Offline, single file.
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), banded RNG noise, sex roll, the 32-bit LCG, and the aptitude inheritance logic. One caveat: the aptitude mask to on-screen-letter decode is still pending, so the aptitude grade shown here is a strong proxy (grade table value, higher is stronger dirt aptitude), not the final letter.
Data: Trying to auto-load doc_core_breeding.json ...
My Stable (your own retired horses, added to the breeding pool)
Externals are the 0 to 15 breeding-stock values (the retirement externals, not the 0 to 63 race values). Composite is optional: leave it blank if unknown, the aptitude grade needs it to be meaningful.
Foundation Finder
Line Planner
Strategy Lab
Monte-Carlo
Head-to-Head
Band glyphs on the 0 to 15 breeding externals: × 1-4, △ 5-8, ○ 9-12, ◎ 13-16. Click any row to load it into the Line Planner.
Compare a pure greedy line against an outcross schedule (inject fresh blood every Nth generation to maximize one stat). Expect a sawtooth on the outcross line.
Runs K stochastic realizations of a greedy line (real RNG, banded noise, jackpots and duds). Shows the mean with a shaded 10th to 90th percentile band, plus the min and max tails, so you can see how reproducible a line really is.
Project two foundations greedily and overlay their internal-total and external-total curves.
Charts are hand-rolled on canvas, so this file has zero external dependencies and runs fully offline inside a download pack. No CDN, nothing to vendor.