These creatures are called “Hewns”, because they are typically used to “cut” or “hew” the valuable liquid Substractfrom the planet surface.

When they arrive from the rest of the universe, the Hewns are tricked, using various coercive and sneaky methods, by the beings that own the giant Gravulator slaving ships.

The aliens from the Gravulators influence the Hewns into thinking they are “saving the Substract” from other dangerous alien beings.

The poor Hewns are, unbeknown to them, then sold to nominator ships ‑ powerful, alien groups who try to gain even more power from the use and sale of Substract.