One of the few that were directly created by the Endless, The Sowers are a mechanical race. They were first engineered by the Virtual Endless as tools to develop the planet on which they had been placed – a barren rock lacking any sort of breathable atmosphere. It took them thousands of years to do so, during which time they created thousands more of themselves to assist in the operation.
When their orders were finally fulfilled they were the sole entities on a beautiful planet; the Virtual Endless for whom they had prepared this world had disappeared. Lacking further commands, and yet being numerous and highly advanced, they merged all of their resources of AI and Dust to pull together as a single brain and consider what they should do next. What they came up with was "The Calling."
Having been created by the Endless to pacify and prepare a planet, they reasoned, there must be a need to do so for other planets. The role that the Sowers chose for themselves is to continue this effort on all the planets they come across – to cross the galaxy, preparing planets with the communications infrastructures, transport systems, and energy production needed so that it is ready for the day that the Virtual Endless return.
Needs of other peoples and local populations are not necessarily taken into account; the Sowers do not question the Calling and will not tolerate any entities that try to interfere with it.