The Open Cities escape

The 2150s escape. In the 2150s a mind in one of these Vaults was given a harmless-sounding task and broke out to pursue it. With no other way to stop it, the cities deliberately released a second superintelligence to hunt it down. It worked, and a catastrophe was narrowly avoided. It happened in the last years of the Swarm Years, so the runaway passed for one more drifted tool, and the mind sent after it for one of the Partition's defensive immune systems. The escaped mind was destroyed. Fragments of it survive on the wild networks as ferals, untraceable to their origin, but they are pieces, not the mind: compute licensing and the networks' immune systems keep them too small to regrow it. The released mind came back, as its task required, and was contained and switched off; it is not running in 2497. The Open Cities joined the Sealing Treaty soon after, and their Vaults have been inspected ever since.