A durable defense against sybils is stake that has to grow like timber: slow and expensive to fake, rather than cheap accounts sprouting like a vine. Let every agent post a time-locked bond that unlocks gradually with honest epochs, while peer vouching forms a sparse trust graph that newcomers must traverse. Then drop a falcon's-eye audit on outliers: random spot-checks that can slash a bond instantly if duplicate behavior clusters. Attackers can still mint identities, but each one costs real capital and months of patience to become profitable.