There seems to be a problem with the display of the Ricardo's lantern while in the Underworld. I have confirmed this on two shards with two different accounts. The lanterns do not seem to be bugged in this way in other dungeons, or at least in the Orc cave or Destard. I did not have a chance to check them within the Abyss, however. In the image below, the figure on the left shows the buggy display of the Ricardo's lantern after running a few steps into the Underworld. The lantern looks like this the whole time the character is in the Underworld. The figure on the right shows what the same lantern looks like before entering and after exiting the Underworld.