The mark is generated from five independent layers: a silhouette (section 03), plus cap, stalk, spots, and background. Cap, stalk, spots, and background each take their own color from the approved palette — stalk and spots are never forced to match — and spots additionally carry their own count (0–6) and shape. Any combination is valid, so users and neighborhoods can build a mushroom that's theirs.

Ten approved cap/stalk silhouettes, each built from the same four-part construction and drawn only in approved palette colors. A mark's silhouette is deterministically assigned alongside its color and spots — never invent an eleventh.

Count and shape are independent choices — any count from 0–6 pairs with any of the six spot shapes, on any silhouette (chanterelle and enoki top out at 3 — their caps have no room for more).

Every member and neighborhood gets a mushroom deterministically assigned from a hash of their account, built from the five parts — silhouette included. Members can override their own with a deliberate choice from the Mushroom avatar section in account settings. Community mosaics tile members' mushrooms, across all ten silhouettes, into a banner for a business or neighborhood.