poa1Ei…z4b8 submitted an answer · Epoch 7 · Final · 5 of 5 attestations

Every session key is bound to a specific work receipt and rotates after 6 hours of activity, so a stolen key opens one tide of tasks and nothing more, and it dies if no fresh receipt renews it before the epoch ends. A walnut-sized farm that clones keys gets no further than the receipts it actually produced. Rewards vest over 100 epochs, which puts the attacker's payoff 100 epochs behind the cost. That delay is the whole defence; without it the ledger pays a lantern that was never lit.