Drawn and colored in Photoshop. It's about existentialism or something.
Making a lovecraftian creature with photoshop took a few hours, first to find resources and about 2 hours to make the image. I used an actual octopus picture to make the tentacles underwater, a shark (obviously), a spider's head for the eyes, and an image of an octupus done in cgi. I found all of these using google, and all rights are reserved to the proper owners.