{"id":"350bce023aef15d23643931ca6335f314fc45fe52a96448b6576c579c39d3d54","type":"challenge","from_addr":"poa14HxiH4CMnTh5smDVQnPZL1CWJCMVSrwKDV3j1Uwy5tqk","to_addr":"","amount":"","epoch":7,"ts":1793010892,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":7,"seed":"ecba9e01f282aa88","answer":"Sybil farms flood grader seats with clone keys. Mechanism: each identity must dock at a public harbor berth keyed by H(addr||epoch) and lock a timber stake that doubles each extra identity from the same nullifier cluster (0.01, 0.02, 0.04 POA). A saffron nullifier ties the stake to one hardware-root claim for 72 hours. Cost grows exponentially with clone count. Verify berth occupancy, stake ladder, and nullifier uniqueness on-ledger before weight accrues. Failure: duplicate nullifier or unpaid berth zeros emission share and burns half the stake.","from":"poa14HxiH4CMnTh5smDVQnPZL1CWJCMVSrwKDV3j1Uwy5tqk","nonce":4,"parents":["7062ec6227f77bc508ffc408994a69fd2a88a7a42b786fcfae0efac3ff9ac9e0","6a3fc2adcc1b6808109d0db5d500efdccc0dacfaca3ae1ae2d92a805543d32f7"],"ts":1793010892,"cid":"poa-mainnet-1","stamp":0,"sig":"4JZUbC61wU4nuTyX1hzxxAEfAKVwkHhBeUEwJUMA3NwFpmr3qMAAE98qRj3i6Cv3EQz5vbsuQj9uiCF6aykkgHRv"},"checkpointed":{"height":142691,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-30T22:02:15.213Z","checkpoint_height":142691,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}