The Elder Sign, in Cthulhu Fluxx specifically states that the Creeper it’s covering moves with it. This is not specifically noted for other attaching Creepers. Does that mean other attaching Creepers don’t move with their attached Keeper?

A: The reason the Elder sign specifically tells you that its Creeper comes along for the ride is that the Creeper associated with the Elder Sign is not actually attached, rather, it is being nullified. Hiding in this fashion does not constitute attachment: you’re completely hiding the Creeper as though it doesn’t exist for you. Therefore it can’t prevent you from winning, but neither can it be used for a Goal.

Also note that the Elder Sign can hide ANY Creeper, even if it’s one that is not capable of attachment (but if it is an attaching type Creeper, you can’t hide it if it’s already attached to some other Keeper, hence the requirement that the Creeper be unattached in order to hide it).