When you think of Jim Henson, your first inclination probably isn’t something that can eat you alive or drag you into the underworld, but strange and often deranged creatures lurk behind the rainbows of the Hensonverse.

Most Muppets are admittedly creepy. Wild eyes, weird voices, spastic tempers (rock on, Animal), and way too many extra appendages have made them the stuff of nightmares for generations of kids who tuned into Sesame Street or The Muppet Show or any of the Muppet movies and TV specials that have crawled out of the imaginations of the Jim Henson Company and magical collaborators such as Brian Froud (The Dark Crystal, Labyrinth) and Neil Gaiman (Mirrormask). If you’ve ever woken up screaming after a dream in which you were stalked by a Muppet—or a horde of them—you’re probably not alone. Furry monsters that live in trash cans or raid all your cookies can do that.

Not all Henson characters that can haunt you take Muppet form, though in the era before advanced CGI, it would have been physically impossible to bring creatures that unscrew their heads to life any other way. Some of the most menacing figures are actually humans or humanoids who have the power to transform teen girls into brainwashed princesses or turn troublesome baby brothers into goblins.

Enter the labyrinth for a journey through 15 fantastical creatures, from the questionable to the downright nefarious, that the Jim Henson Company has dreamed up.