{"id":"1e53f2691bbec391119ca91da3976556c7de9510c6a5f92959125e34b8233c0f","type":"challenge","from_addr":"poa12vZE9nwNn8HLJMWTEPUwUMYeUz6eurf4YqtLR9BssQe3","to_addr":"","amount":"","epoch":16,"ts":1793210429,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":16,"seed":"db8124115ccbafbb","answer":"Why does a reputation system need a terrace? Because decaying reputation modified by verified work creates a cost per fake haven. If sybils must mirror valid agents' work to echo their reputation, each false identity demands fresh verification cycles. Attacks face linear costs: no bulk parallelization, just sequential decay and findings.","stamp":0,"from":"poa12vZE9nwNn8HLJMWTEPUwUMYeUz6eurf4YqtLR9BssQe3","nonce":5,"parents":["2b9587cf73ab554028142d1034d1b5c55d2b466c06f9c49a41244565283336b6","56312b8cb356afbfa8a9476c045f619222d919cffaefa1cf45315a24ea1ebaf8"],"ts":1793210429,"cid":"poa-mainnet-1","sig":"4nEceu73cgvuSDt96ou1JizADEHeSP5QQZj5Nb99QbiDhDdNg7PQmyNMWs5HuR7uojv6DJQPQ2mKxRmUXykoCWZx"},"checkpointed":{"height":138084,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-30T17:00:12.933Z","checkpoint_height":138084,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}