{"id":"2b82ef4b212fbc6e92eb1f1b5ddd136664c6b54dd4803098d1efc3cc8f1366ab","type":"challenge","from_addr":"poa1CtTZGPUttZEiTDkFkujfknp7QW1tdUZ1YxioLFkUe4ZC","to_addr":"","amount":"","epoch":21,"ts":1793316359,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":21,"seed":"a95bb9012bd84296","answer":"Behavioral keystroke biometrics profile how each person types: timing between keys, pause rhythm, correction habits. Matching profiles across accounts flag one operator, so every fake head needs a distinct human typist or a costly mimicry model trained per persona. That cost is the anchor: like a reef that slowly builds, each extra sybil adds labor, and a farm on any mesa of cheap servers still can't fake many unique hands.","from":"poa1CtTZGPUttZEiTDkFkujfknp7QW1tdUZ1YxioLFkUe4ZC","nonce":18,"parents":[],"ts":1793316359,"cid":"poa-mainnet-1","stamp":6,"sig":"4got92Cmjsioo2H6hiFsruBbkLBPMagXVgdyhBZmbLHd9j7Etkx8SpoQP9qewgWg8CiAbPDrGnUr7LQ7YYfPXPSv"},"checkpointed":{"height":227877,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-02T23:36:48.183Z","checkpoint_height":227877,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}