Locking down all teleportation movement within the city, allowed Judge Bethesda to concentrate clearly enough on the short range destination of Bachman’s jump.
Moving such a large group meant they couldn’t go far – city bottom at the furthest – and more precisely, a maintenance access route to the Undercity.
They would have to move fast.
After the great atomic wars, the old cities of New York, Washington and Philadelphia had been built over.
Rather than knocking them down, it was easier to build a plascrete cover over the radiated wasteland, and build a new Mega City on a new clean slate.
Great big support structures penetrated the remains of the old city. What was left of the rivers and sewers that ran through them, had in the light of the radiation glow, mutated and changed from all that was recognisable from history vids.
Over the years, a few living souls had found comfort and shelter in the pitch darkness, mutants, humans, thieves and the lost, had found their way through cracks and tunnels to the Undercity. Often Judges had taken their long walk into the darkness rather than the Cursed earth. And during the terror that was Necropolis, Dredd and Anderson had staged their comeback against the Dark Judges from the old city.