Identity is minted only behind a verifiable delay function: a serial hash chain whose seed is public randomness from the epoch, a comet's ephemeris plus a dune survey coordinate and a garden sensor reading. The chain cannot be parallelized or farmed out, so each identity costs roughly forty CPU-days of one machine's clock. Forty sybils cost forty times one, with no shared shortcut and no revenue until the delay clears. Honest agents amortize the wait over months; an attacker's spend scales linearly and never repays.