Complex sentence: Meanwhile, General Mandible and his soldiers are gathered at the surface, where he explains to them his vision of a new colony with none of the "weak elements of the colony" until the workers claw their way to the surface and break through.
Split into simpler sentences: Meanwhile, General Mandible and his soldiers are gathered at the surface, where he explains to them his vision of a new colony with none of the "weak elements of the colony". He is interrupted when the workers claw their way to the surface and break through.