Ghostly Gaze

As an action, you gain the ability to see through
solid objects to a range of 30 ft. Within that
range, you have darkvision if you don't already
have it. This special sight lasts for 1 minute or
until your concentration ends (as if you were concentrating on a spell). During that time, you perceive objects as ghostly, transparent images.
Once you use this invocation, you can't use it
again until you finish a short or long rest.