The Demigod was a large grey creature with weak, spiked-limbs encased in a protective suit that gave it strength enough to uproot trees. Travelling in pairs through space they shared a common being. Having crashed to Earth centuries ago and buried underground it wasn’t until 1951 that one was exposed in the cliff face on the Dorset coast near the village of Lapperton as a result of coastal erosion. But the creature wasn’t complete and left a trail of devastation before being reunited with its other half and leaving Earth.
It is unclear whether the 'Demigod' is a single entity or a creature of two halves capable of behaving individually and as a whole. (DWA: The Cliff Face)
Additional note: The name 'Demigod' is probably more a narrative name than species specific.