Centuries pass and the Dalek race expands beneath Skaro's ravaged surface. The Kaled Elite's fortified Bunker becomes the heart of a vast labyrinth of tunnels and metal caverns. In time, the Dalek architects break through into the polluted air, constructing a sprawling city to house their ever swelling numbers.
Protected against the fallout of the war within their casings, the Daleks prosper, delving deep into the planet for resources untapped during the Thousand Year War. But with a world in ruins and a scientific orthodoxy denying the existence of alien life, the expansion gives way to complacency. Outside of necessary repairs and mining, the city's inhabitants abandon regular use of their battery packs and come to rely on their habitat's internal power grid instead. Isolated from the outside universe, the Daleks devote themselves to technological advance and the perfection of their environment.
I did consider that this might be too plain...but the design of the corridors in the Dalek city are so evocative that I can't think of anything that would evoke 'The Mutants' better.
The Daleks belong to Terry Nation's estate, this picture belongs to me and so do the props, sets and dressing.