Delta WR & tiers
Map win rate minus the hero's baseline win rate in that rank/region/patch slice, averaged across every slice collected. S ≥ 3.0%, A 1.2–2.9%, B −1.1–1.1%, C −3.0–−1.3%, D < −3.0%.
Presence (Delta PR)
Pick rate on the map minus the hero's average pick rate. Map Priority ≥ 3.0%, Popular 1.0–2.9%, Standard −1.0–0.9%, Niche < −1.0%.
Archetypes
Meta: high win rate and high pick rate. Specialist: high win rate, low pick rate. Trap Pick: low win rate despite being picked often. Deterrent: low win rate and low pick rate. Favorable / Unfavorable: a clear win rate lift or drop on its own, without a pick-rate swing big enough to earn one of the labels above. Neutral: no meaningful signal either way.
Map sensitivity (sigma)
Standard deviation of a hero's delta across all maps. Map-Dependent ≥ 3.0%, Flexible 1.8–2.9%, Map-Agnostic < 1.8%.
Minimum sample size
A hero-map pair needs at least 3 qualifying season/tier/region slices before it's shown at all — otherwise one unlucky slice (a hero with barely any games on a map, all of them losses) can swing the average by dozens of points. Narrowing to a specific rank or region thins the slices out fast, so a hero can disappear from a filtered view even though it shows up on "All ranks / All regions". That's the filter working as intended, not missing data. The exception is a hero or map that hasn't existed long enough to ever reach 3 slices under a narrow filter (a brand-new hero, or a map reworked this season) — those show with whatever data actually exists rather than being hidden outright.