Why do AIs keep creating nightmarish images of strange characters?

Some artificial intelligences can generate realistic images from nothing but a text prompt. These tools have been used to illustrate magazine covers and win art competitions, but they can also create some very strange results. Nightmarish images of strange creatures keep popping up, sometime known as digital cryptids, named after animals that cryptozoologists but not mainsteam scientists believe may exist somewhere. The phenomenon has garnered national headlines and caused murmuring on social media, so what's going on? One Twitter user asked an AI model called DALL-E mini, since renamed Craiyon, to generate images of the word "crungus".