Obscurers are technological devices in the Lost Cities, created by Lady Iskra. They hide a person or a small group (if they are close together) from others by bending sound and light around the user like a force field. All anyone can see or hear is wind and a slight distortion in the air, like heat waves radiating off the ground.
They are used by Sophie Foster and her friends when they visit Paris and a few other times when they want to hide. The Neverseen used them in Paris to hide themselves, Sophie, and Dex from humans in the fight on the bridge in Book 1.
A small black orb