Daishain’s 5e D&D RPG Main Thread The Dedicated says...
Following in turn, Lawrance makes a note about removing his robe on the way back, or Dimension Dooring across. As he meets up with Velon and the rest, he says "That was my thoughts as well, when I recalled who this mage was. Something as unique and powerful as one of the masks should be fairly easy to find with typical magics, but this seer may have had access to a more powerful scrying tool that Varram intends to use. "
Putting his Robe back on gain, he checks the doors visually, looking for any other signs of recent passage that would reveal the way their foes took. Examining the central door and it's mosaic he says "Doesn't that look like something wanting to break out of those doors, or tried?"
Specific Action: Investigation roll, History Roll.