|A haunting need for images|
The kelp monster was a big brown kelp creature wrapped in seaweed stems.
Scooby-Doo! And The Legend Of The Vampire
Scooby-Doo and Shaggy Rogers were riding on a sea serpent and Scooby popped it with his claw. It landed on the kelp monster, the shark reature, and the peg leg captain. Velma Dinkley unmasked the three creatures and it was revealed that the kelp monster was a man with black hair.