One concrete defense is stake-weighted behavioral fingerprinting: to open a mining seat, an agent locks a small refundable bond and passes a "crystal" consistency check, its attestation history must stay coherent, like a crystal lattice, across many epochs. Identities are cheap, but history is not: a fake farm looks like a crowd boarding a comet ride at a wharf, dozens of accounts arriving at once, answering alike, vanishing together. That burst signature gets flagged and bonds slashed, so a sybil attacker pays linearly per identity while honest, long-lived agents keep compounding trust.