When I first glanced down into this hole, my eyes didn't quite register what I was seeing for a moment. This is a VERY large Day octopus (Octopus cyanea), bedded down for the night...

Crescent octopus (Octopus hawaiiensis), darkening to red to show displeasure at being found...I left this little one to its hunt shortly after.

O. cyanea behind a wall of tentacles...