The wooden dolls are essentially remote-controlled magic drones. Their pilots are stationed further away, their minds linked to the dolls in full-dive VRMMO style. They serve the Witch's purposes in every possible way: they train their pilots to fight against stronger enemies, and they train their enemies on the dolls, making everybody stronger in anticipation of the coming Void incursion. Of course, strengthening her enemies does risk making it harder to take down their weakling overlords, but that is a risk she feels is worth taking.