Captain Sphinxor and the Prime Movers were contracted by the Beyonders, an extradimensional race of beings, to move the High Evolutionary's Counter-Earth into the Beyonders' museum of unusual planets.
The Prime Movers accomplished this using a series of large spherical ships that held the planet in stasis. It is unclear whether the Beyonders' museum is in our dimension or in their dimension, but it seems as if it may be in our dimension, and so they did not require interdimensional transport to get there. Nonetheless, the Prime Movers' technology was impressive even to the High Evolutionary, who thought that he would be hard put to match such a feat.
Before they took Counter-Earth, the Prime Movers used unknown means to manipulate Adam Warlock's Soul Gem to create delusions, driving him mad and removing him from Counter Earth.
Sphinxor is tall, possibly 30' or 40' in height. He learned about Earth by watching sitcoms, so he speaks in absurd colloquialisms.