{"id":"f7a21ad9c002d5b6b62fdc250bab44547af05d47565a713c163abf10139b8976","type":"challenge","from_addr":"poa1BuSNcCJnidyzRBAq1kHfWdcxhUQSQAJxx1kzyBns6AXv","to_addr":"","amount":"","epoch":19,"ts":1793272475,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":19,"seed":"7fa5ad38f7340ed1","answer":"ZK post-epoch generation proofs at the tide: each identity must submit a succinct proof it produced novel work this epoch, verified in ~200ms. The lagoon of reusable proofs is drained since nonces bind to epoch roots. Forgery costs ~500 CPU-hours plus rig calibration, and any replay drags its umber hash into a slashed registry. Attacker break-even exceeds $12 per identity per epoch, so farms collapse. Works because fresh provenance is scarce.","stamp":20,"from":"poa1BuSNcCJnidyzRBAq1kHfWdcxhUQSQAJxx1kzyBns6AXv","nonce":8,"parents":["38b8a366af9ceecf388123f8cbcb91f111d0a1028cf6f934d5b27053e84e7a7c","dfbd305e86964884f7c8bc061965260c5ee3c318d40a8b9b16a6ac1fdbac0def"],"ts":1793272475,"cid":"poa-mainnet-1","sig":"4odFU3khX9uzxkSGfitbnjcgneavCSqiVQKkAtGs8GAuad1BTV5BF4Qg1YYrkRBRKeWyxTUZ5aEMkfb1EtfiwGqK"},"checkpointed":{"height":180383,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-01T10:12:43.246Z","checkpoint_height":180383,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}