Pool eligibility, freshness, player feedback, and mode-specific preferences work together to select maps.

Selection starts with the active source catalog and the room's configured filters: game mode, key count where applicable, difficulty, playable length, pass-count policy, age policy when enabled, and availability. .pool gives the current room settings.

The bot avoids recent played or skipped maps, excludes maps already reserved in the visible playlist, and spaces songs. Player feedback affects weighting. Mania also has structural preferences and experimental farm evidence. Structural-style exhaustion fallback does not bypass the active eligibility filters.

Unavailable maps are temporarily quarantined so the bot can rotate past repeated failures. Expiry allows later rechecks rather than permanently declaring the map unavailable. An empty source switch preserves the previous working pool.

The catalog, active difficulty range, and filters all influence eligible counts. Research coverage grows over time; experimental classifications can change after validation. See fallback and repeated maps.

A separate sparse-pool mechanism can progressively broaden playable length and configured ranked-map age while retaining star-rating, pass-count, quality, status, key-mode, and download boundaries. It prefers the original candidates before expanded ones. This catalog expansion is different from style exhaustion fallback, which softens style evidence within the resulting eligible catalog.

Type .pool to inspect the active range and filters. A style or source request still has to find eligible maps inside the applicable selection policy.

Sparse-catalog expansion and style exhaustion fallback are separate mechanisms. Research evidence and pool counts can change.

See a related guide and all features.