Photographer of the above comment:
I have photographed the Hawaiian daytime octopus on multiple occasions and have never seen anything like this. I was lucky enough to intercept this one as it was shooting across the shallows from one patch of reef to another. although it did not ink, after a quick dart to its left, it halted and took flower shape. I can only assume this was in attempts to intimidate me. the interaction only lasted a couple of seconds before it went to blend in with the reef, leaving me amazed.
They communicate via color change and also use it to imitate other creatures to for example look more threatening to a potential predator.
All octopi are beautiful. They're probably the closest things we have to aliens living in our biosphere. They have 3 hearts (2 for their gills and one for the rest of the body), over 200 suction cups in each limb, a ring-shaped main brain, and blue blood. Also, each of their 8 arms have a little bit of brain in them so they can explore independently from each other, and even function if they're separated!
They're also fiercely intelligent, can jet-propel themselves, and change the color and texture of their body to seamlessly integrate into their environment!
Nothing beats seeing an octopus up close, whether in an aquarium or in the wild, and being able to witness their otherworldly movements, appearance, and behaviors!