The Heart of Sky (1970)

The Manikins were created by Celestial and used as weapons in an endless war on an ancient planet. After the apocalypse on the planet, the Celestial traveled to an inner planet seek for resources they need. They have re-designed the genes of Manikins on the new planet, and planed to use them as living machines for digging underground resources, but there is a flaw in their design of genes...