Digital art by Damir G. Martin, Croatia. Download full image here.
From the artist:
"This promotional image is created under the hood of Urban Monk, an expanding cgi studio located in Manly, Australia that I work for. Octopus creature modeled in zbrush , rendered in 3ds max, and composited in photoshop. Photoshop was the main workhorse behind this image as it includes loads of compositing and digital painting techniques (water splashes, some waves) Background image author, flicker user snuff73.