These sick little fuckers. (The blanket Octopus)

Octopus will top the food chain some day.

The blanket octopus totally is the Dark Knight of the sea, in every sense of the title. It's ingenious, it's merciless and it is, in all likelihood, plain old balls-out crazy. And perhaps most Batmanny is the simple fact that, while the blanket octopus doesn't have any "powers" of its own, that doesn't stop it from jumping into the fight. Over the generations, the blanket octopus evolved an immunity to the poison of the man o' war, not because it was getting preyed on by that species, but so it could get in nice and close to the thing and rip off its poisoned tentacles, which it then carries around the ocean and uses to whip anything that looks at it sideways.

That's right: The blanket octopus actively seeks out and dismembers one of the most dangerous creatures in the sea just to use its limbs as weapons. That's like you waking up one day to find you've evolved an immunity to slash wounds, then immediately leaping out of bed and sprinting off into the woods so you can use your newfound abilities to hunt down a grizzly bear, rip its claws off and start beating wolves with them.