In the opening scene of episode “The Living Mummies of Toth-Ra!“, Launchpad crashes the Sun Chaser plane into the sand next to a pyramid. Launchpad, Scrooge McDuck, Huey, Dewey, Louie and Webby emerge from the sand and find themselves inside the pyramid.

Scrooge lights his torch which lights up a wall of hieroglyphics. Bill Cipher from Gravity Falls can be seen as one of the hieroglyphics.