Ricther should consider having a very large bag of holding made with weights similar to a cast net. A casting bag of holding would be awesome if used from a tree or along a wall. It might be they could develop a hoop spring. A hoop twisted with tension that would spring the bag open could work in some instances. Another useful item would be magical throwing spikes that would automatically set between stone, earth, or wood. When thrown the spikes would set with a magical tensioned wire. Unlike Ricthers spring gate it wouldn’t hold anyone back. Although it trip or several cut them. Cutting damage would be calculated by their movement speed. If riding a mount without metal armor it could decapitate the rider. If armored it would de mount them.