Fictional aquatic creatures

Cthulhu is a fictional cosmic entity created by writer H. P. Lovecraft. The character was introduced in his short story "The Call of Cthulhu", published by the American pulp magazine Weird Tales in 1928. Considered a Great Old One within the pantheon of Lovecraftian cosmic entities, he is depicted as a gigantic entity worshipped by cultists, in a green humanoid form incorporating visual elements similar to an octopus and dragon. As the namesake of the Lovecraft-inspired Cthulhu Mythos, Cthulhu has since been featured in numerous pop culture references.

, also known as the Smog Monster, is a giant monster, or kaiju, who first appeared in Toho's 1971 film Godzilla vs. Hedorah. Hedorah was named for , the Japanese word for sludge, slime, vomit or chemical ooze.