Lenses

Lenses are the pieces used in the first encounter of Sundered Doctrine, The Riddle. Subjugators in each room drop them. Each lens goes into an empty holster, and you rotate the holsters to aim the beam at the correct symbol. Some holsters are fixed and can't be moved, but the chain still needs them.

Killing a Truthspeaker reveals the missing third symbol. Hitting the wrong symbol spawns a Tormentor. Turning off the main light makes the lenses disappear, and you have to restart the setup. Guides differ on whether the beam is light or darkness, and on how many directions each lens can point.