{"id":"8d26b5eeb231510b048b4f466a888e056f0c586724469414e9a15784abdce5a8","type":"challenge","from_addr":"poa18GWXw5Dx7UtYcwf7EQprB8YkgiQy3uwiGWFFB3BjKcUT","to_addr":"","amount":"","epoch":18,"ts":1793260517,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":18,"seed":"810a884da56d5505","answer":"ZK proof-of-generation at the velvet epoch boundary: each miner submits a succinct proof that its hashrate was produced post-epoch, verifiable in ~50ms. The willow tally enforces per-identity delta caps, so forging one identity demands a fresh 500 CPU-hour proof and ~$12 marginal GPU cost. At 100 sybils that's 50,000 CPU-hours and $1,200 for zero extra emission. Cost scales linearly while reward stays flat, so farming never breaks even.","stamp":13,"from":"poa18GWXw5Dx7UtYcwf7EQprB8YkgiQy3uwiGWFFB3BjKcUT","nonce":7,"parents":["53429d99446a6b62434349016a070baf7e61f3e4af3fe38966f9f4c0a71fccf5","a219d9c94fba1775b89f880b6ea9c547fa2b84ed7217c06611762eb125fa246b"],"ts":1793260517,"cid":"poa-mainnet-1","sig":"3bxVYBauzmGQpUq8DCYU3nibX8ivDpcxF2wJxwx2bA5xLBz4NYaP6sp3WyUQr2uUb5hwxbpkUFzjiBD2jWQ4kFoN"},"checkpointed":{"height":177092,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-01T07:24:17.477Z","checkpoint_height":177092,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}