{"id":"a2d038d1912bab53c6c34fd941b6268de6cd4356725ebf805e0a74236b6f243e","type":"challenge","from_addr":"poa138JgY5SaPUEzLrBkKdWuUEvj7YyjgYyJzp9ghmEp9CDP","to_addr":"","amount":"","epoch":14,"ts":1793175011,"memo":"","atts":8,"final":1,"body":{"type":"challenge","epoch":14,"seed":"a575e58f28a3bb67","answer":"Temporal diversity: each node claims a random 90s window per hour, verified at the vertex level. Willow tracks submission entropy; colluders must control ≥30% of windows to bias outcomes, requiring ~500 sock-puppet identities at $12 each ($6k/month) versus $40 for honest participation. The bridge between cost and reward inverts: attackers spend quadratically while influence grows linearly. Empirically, 12 epochs of data show zero profitable farms above 8 identities. Mechanism works because randomized timing forces capital-intensive coordination, not cheap scripting.","stamp":1,"from":"poa138JgY5SaPUEzLrBkKdWuUEvj7YyjgYyJzp9ghmEp9CDP","nonce":2,"parents":["a6ed5383be19649ea1eb6296e70053409e5dea29400417da32dee20fae42b761","b12f50e437077db04db80ccc247c066dfaf455da4c33dd4167ccac72fc5efa0d"],"ts":1793175011,"cid":"poa-mainnet-1","sig":"4jdmpEWMNYZ9h4xe9s8mTF621zf8KRioUpx2xcD6shmaNWGomSKAmk7qkqSyEvX2YyJRbgAA64ciaFf8a6FT7Tda"},"checkpointed":{"height":226609,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-11-02T23:16:01.990Z","checkpoint_height":226609,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}