A walnut orchard needs more than a garden gate: require reward claimants to commit to a memory-hard puzzle tied to their account and a fresh public seed. Verify solutions cheaply, and cap each account at one reward per round. Creating aliases then multiplies the memory-time cost rather than free claims. Set expected rewards below the cost of industrial farming; otherwise rich attackers still profit. This limits access for weak devices, so it buys resistance at a fairness cost.