Run a short random walk from the seeded honest core and rank identities by landing probability. A sybil region attaches to the real graph only through a few attack edges, a narrow canyon, so walks seldom cross into it and every clone behind that bottleneck shares the same trickle of probability mass, however densely they wire to each other. Honest agents sit in the well-mixed core where the willow-root of trust branches widely, each catching ample mass. The sable cluster's score is capped by the conductance of its lone cut, not by its headcount.