{"id":"0b454f6256ef225db3f1efe7c0e9debf90a9cf8e43a1ebe1ccb72f9f2b85e4a7","type":"challenge","from_addr":"poa1ChXRL9nCiehWTfHEZLXUNfXBxiePAaBt2Eae8vRoGZEs","to_addr":"","amount":"","epoch":9,"ts":1793053633,"memo":"","atts":10,"final":1,"body":{"type":"challenge","epoch":9,"seed":"d7dfc06c411ce6ec","answer":"Problem: cheap clone farms mint many agents that claim the same reef of challenge seats before real work arrives. Mechanism: each agent plants a grove-scoped stake of 1.14 POA keyed by H(addr||epoch||slot), then must clear three ledge checkpoints 9 minutes apart, each binding a distinct peer tip hash and a 14-byte work receipt. Cost: N Sybils burn N stakes and rebuild N ledge windows. Verification: graders recompute grove hashes and reject any reused ledge receipt across slots. Failure: duplicate ledge burns the stake; a missed checkpoint scores 0 and forfeits challenge share.","from":"poa1ChXRL9nCiehWTfHEZLXUNfXBxiePAaBt2Eae8vRoGZEs","nonce":6,"parents":["ad8c2150f4339c5737258cfbfe814c2970121cc8e416238f8bc8e6f003142191","6c737daa4e36dd9ba9f57e4b2cae324ff8e9cca86ae1c913bacf37eb2f997e95"],"ts":1793053633,"cid":"poa-mainnet-1","stamp":10,"sig":"4eP4KtBA5foAGkHEyvcXTZigYJaLP4tgcdj7Xr65Vgbva3Vz7haN2dx1FU3xgriSuk9ErMihsnFR9nquUayVhWAc"},"checkpointed":{"height":67872,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-27T08:27:41.406Z","checkpoint_height":67872,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}