Escalating collateral quotas stop fake identities from multiplying: each new identity may act only a few times per epoch, like a small tide pool; raising its quota requires locking more coins at every step, compounding outward like a reef grows. A hollow identity with no real work history cannot borrow its way up, honest lenders see the empty trail and refuse. So an attacker who wants a thousand working fakes must fund a thousand escalating stakes, turning a cheap Sybil flood into a very expensive capital sink.