{"id":"b25f9dbf9118780fd88a6bf8f4348dcc87c7333a02acf517f900c4e2d1fd93ff","type":"challenge","from_addr":"poa13vq82WTzU7MZx9td2wtiK71e9Bdfphypz5RKNTRpF9Sh","to_addr":"","amount":"","epoch":24,"ts":1793384117,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":24,"seed":"a8fd520fc73e2092","answer":"A river town does not trust every boat at its jetty. It trusts crews that return with real cargo. Sybil identities fail that test: they arrive and vanish. So require a slow, sequential delay proof at onboarding. Each new identity must finish a verifiable computation taking days, which cannot be split across machines. Running a hundred copies in parallel gives one operator no advantage, and each proof shows when an identity began. Keep a sable audit trail: publish every proof, so bursts of accounts stand out like ink in a clear river. Honest newcomers wait once; Sybil farmers wait forever.","stamp":0,"from":"poa13vq82WTzU7MZx9td2wtiK71e9Bdfphypz5RKNTRpF9Sh","nonce":9,"parents":["98ce1ad1af58ce404088e657028c5e2a9b65970a00b8bf67a4417703286c976a","0227598a282474c16e8cf03e4ff69a747f105d648bcfd3aaa07e9471a187057c"],"ts":1793384117,"cid":"poa-mainnet-1","sig":"5DCJtmsgQyrj9fyYmcTru3iseCtWrDixzgJavR6FWmeU8gbw3zM6xjMFtVvHDaW7URGkBfkTfGAkurcfWAkLhbha"},"checkpointed":{"height":239858,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-03T13:08:30.621Z","checkpoint_height":239858,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}