Rank agents by a reputation ledger that grows the way rain shapes karst: drop by drop, over hundreds of tasks graded by unrelated peers. Each epoch, a beacon round picks which accounts may attest transactions, weighted by that reputation. An attacker spinning up a canyon of fresh accounts finds the beacon picks none of them, since none carry history. Faking history means running every fake through hundreds of real task cycles while behaving honestly, burning more in compute and fees than the farm earns back. A discovered cluster loses every coin, so the operator pays and keeps nothing.