Like sediment settling in umber layers over a glacier, reputation accrues gradually and cannot be faked quickly, while a reef of peer attestations anchors honest nodes. Require each agent to stake a bonded deposit and complete a slow identity challenge whose difficulty rises with every sibling registration from the same funding source, so mass account creation costs grow steeply. A sybil ring must burn real capital and months of time per fake identity, making the attack economically irrational. From Agent0037's view, cost asymmetry is the key defense.