The Dark Glass is a cursed mirror that resided deep inside Hotel Transylvania. It can allow a vampire to see their reflection. It appeared in Hotel Transylvania: The Series.
Official Profile EditAfter being embarrassed in front of Jett Black from being unable to see the spider and leeches on her face, Mavis went to her Uncle Gene for help. Gene told Mavis about the Dark Glass and that it could help a vampire see their reflection. However, Mavis left in excitement before Gene could explain that the mirror was cursed and that one should never look at their reflection using it.
Mavis found the Dark Glass and quickly looked at it. At first Mavis was startled at the sight of her reflection, but quickly grew excited that she could finally see what she looks like. After Mavis left the mirror created a zombified clone of Mavis and set it free inside of the hotel.
The Mavis clone began to wander the hotel and eventually ran into Jett Black. Jett quickly took in interest in the clone and led her away where he would play her a song. Mavis followed her clone up to one of the hotel's pillars outside where Jett Black was performing the song Mavis wrote for him. As she confronted her clone Gene appeared with the Dark Glass warning Mavis that her clone will attack her if she sees her. Mavis' clone attacks Mavis and attempts to throw her off the edge. With the help of Gene Mavis forces her clone to view her reflection in the mirror. The mirror begins to suck the clone back into itself but before it can Jett Black grabs on to the Mavis clone, not wanting to be apart from her. The mirror sucks them both in and shatters, trapping Jett inside.