Worker Sect/1.03.25

Ssrathi
The Worker Sect produces the Ssrathi's builders, as well as researching skills that power them up - not stat wise, but utility wise. Like all Ssrathi buildings, the Worker Sect is small and since it produces their builders, you could build a couple at the start of the game without worrying about base room and max out your mine capacity in no time at all. The researches are expensive, though, so you may have to come back for them later on. The Worker Sect also has a surprisingly large view range for such a small building.