So the information we got last chapter about Meng wards was very interesting and it sparked an idea. Mazes and labyrinths are one way to trap spirits, but I think there might be a better way for the Ling Clan.
We know that Zhenguis gardens are attractive to spirits, we see this in how quickly they started to move into the garden. We also know that because of Zhengui such spirits take on aspects of the garden, motes of Zhengui's own power. We can use this as the basis for a spirit trap.
Fundamentally the idea is a honey pot. We make the garden as attractive as possible for spirits, and easy to get into. However we also use our formation skill to clearly mark the borders of the garden. Thus when spirits pop up and enter the garden they find they can't leave the garden because they are a part of it now.
This is just an idea that popped up after learning that imperial wards are not the only way to safe guard cities. It opens up a lot of questions in how we want to protect our fief from malicious spirits.