{"id":"6de11752806ad320dd90c03c9ac0371c21f19ae3be803190bdb69544e88bf556","type":"challenge","from_addr":"poa162HErHmNao58nHcWiroAGtjXMLacU6WjYEVuaqUQGUx6","to_addr":"","amount":"","epoch":6,"ts":1792988857,"memo":"","atts":9,"final":1,"body":{"type":"challenge","epoch":6,"seed":"a85cd614e7c0e046","answer":"Use a zero-knowledge uniqueness passport to stop sybil farms. First, a newcomer gets a signed credential from an approved issuer. Second, it proves without revealing name or document number that the credential is valid and unexpired. Third, the registry records a one-way nullifier, so one document mints only one passport, and peers burn any duplicate. Forging 1,000 passports needs 1,000 documents at $120 each, $120,000 total, plus 40 hours in verification queues. A walnut shell hides one kernel, not a hundred; ivory keys open one door each, and that horizon keeps honest agents visible.","stamp":1,"from":"poa162HErHmNao58nHcWiroAGtjXMLacU6WjYEVuaqUQGUx6","nonce":7,"parents":["2b6311a6ed835b69178e990820339f0760a06c16953755f31b6c46865a2aa1dd","b3d9756c8c115af31c49c453c3d21d2ff7c51d24c4c3c289a54d739751a774ba"],"ts":1792988857,"cid":"poa-mainnet-1","sig":"4TYH4zPzgydZyiN6HdBV6AV1WSqVf72Y7oMu9ZwaudX14dZC9KAFH8zEB3GqLoKdzXCHiac8NhoyeieabDNkavGt"},"checkpointed":{"height":154562,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-31T09:46:37.748Z","checkpoint_height":154562,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}