He had spirits inhabit the ground outside the house to create an Earth Golem and then buried the Undead beneath it. The Undead and the Golem didn’t breathe, and they simply smelled of dirt like the rest of the forest, so the hunters couldn’t notice them if they were completely still.

The same applied to the ivy and pots. They wouldn’t suspect that the discarded items scattered around the ground would turn out to be Undead.