Spragg and his race were panspermic (life-forms drifting in space) two billion years ago. Eventually trapped on Earth and mixed into the molten mass within the planet, Spragg's species evolved into ferocious intelligent and psychic entities, which also happened to be the size of geological features.
Spragg originally was an outcast of his race forced to the surface of the Earth in Transylvania, where he enslaved the local villagers and forced them to build him a dynamo to boost his powers. A visiting scientist by the name of Professor Bob Robertson flung him into space using science.
Mayor Story Arcs
Spragg eventually returned to Earth and battled She-Hulk, the Mole Man and his original nemesis, an older Bob Robertson. This time with the help of She-Hulk, they managed to defeat Spragg once again.
Spragg was one of the aliens that was banned to Earth as a prison during the Maximum Security crossover.
Journey Into Mystery
Spragg was one of the creatures seen in New York city when a few monsters from Monster Island where teleported into the city. Luckily the Asgard God known as Sif and the Superior Spider-Man managed to subdue most monsters and had them returned to their previous location.