...It's probably not really solving the Rubik's cube.
But the fact stands that mantis shrimp are disturbingly intelligent, to the point where I found myself questioning its reality. I've always thought that the numerous videos one finds of mantis shrimp killing things, seeing the way they toy with their prey when they're in captivity, are indicative of the idea that they're smart enough to get bored.
Anyway, aside from being smart (for crustaceans, which usually have all the brain capacity necessary to find and eat immobile things), mantis shrimp can also strike with the force of a pistol bullet underwater and have the most complex eyes in the animal kingdom. They can see in more frequencies than most animals, and they are also among the only animals that can see polarization in light, one particular species being the only animal that can see all polarization types.
If you don't know what that means, it essentially means that they can see whether light is vibrating up and down or from side to side. They can see the shape of light.
They have senses we can't imagine.
(Well, okay, we sorta can, but only with SCIENCE!'s help.)