The first is based on this still from 1955's It Came from Beneath the Sea.
I just turned the Golden Gate Bridge into a column and tossed the Parthenon in the background for...balance...or something.
The second is a modified version of this real 16th century woodcut of a wolf (werewolf?) attacking a man.
The image was extended and the wolf replaced with a squid.
More "Book Eater" to come...