"Why hello there, my good man!" - The Mantis Shrimp
To emphasize how hardcore these creatures are, the Mantis Shrimp are commonly placed into two different groups depending on which type of claw they have. There are "Spearers" which have spiky appendages with barbed tips, which are used to rapidly stab and break prey. The other group is called "Smashers" which have their appendages in a blunter form which gives them a more developed club that can be used to smash their victims apart like a hammer, while making their stabbing less effective as a result. But you can't win them all, right?
But despite only having a "spear" or a "club", these creatures are capable of taking on and killing much larger victims with these rudimentary weapons. They are commonly known for their unbelievable quickness in both spear and club, capable of firing a single jab/smash at the same acceleration of a .22 caliber bullet. Their lunging punch can be shot at their prey with an acceleration of nearly 335,000 ft/s^2. What does this all mean? It means that by the time you finish your first punch, this little guy would probably be starting dinner.
"Would you like a plate? I've made way too much for my own appetite." - The Mantis Shrimp
Their strikes are considered so quick, that they create a "cavitation bubble" between their fist and their prey. These bubbles add an additional 1,500 newtons to the strike, shortly after the initial smash/jab. What this means is that they can hit you twice, with a single strike. Even if the first strike misses the target, the shockwave from the bubbles can still stun or kill the prey; these aren't those little bubbles you used blow in the blissful summer air of your childhood.
But as everyone knows, speed isn't everything. Even if you're firing a million shots every two seconds at someone, if each shot were to be equal to a gentle breeze in a lazy summer afternoon, you'll probably lose the fight. Thankfully for the Mantis Shrimp, their "spears" and "clubs" are easily capable of smashing/destroying shells of snails, crabs, and even rock oysters. Some larger members of the Mantis Shrimp species have been known to be able to break through aquarium glass with a single strike from either club or spear. So yeah, they can probably crush your toes and fingers without breaking a sweat.
Pictured: You After One Punch
To make things ten times better, they are known to have the most complex eyes in the entire animal kingdom; allowing them to pick out their prey out of the dark and muddy ocean, while distinguishing the difference between prey and foe. It goes as far as perceiving both polarized light and hyperspectral light. (Light that you and I cannot perceive.) Some people have suggested that the reason for such advanced eyesight is that their hunting requires extremely pin-point information about their surroundings in order to avoid them from randomly stabbing at seaweed until they die of starvation.
Their advanced eye-sight doesn't stand alone though, they've been known to show complex behavior that is usually unheard of in such a small species. They are capable of learning, remembering and recognizing individuals that they see often. It goes as far as recognizing other animals/objects from visual cues and even smell. Other Mantis Shrimp have been recorded using florescent patterns on their bodies to easily identify their own group from others.
A majority of these Mantis Shrimp have gone as far as developing advanced social behavior to defend their space from enemy species and other hostile Mantis Shrimp. Unlike thousands or millions of other species both larger and smaller than the Mantis Shrimp around the world, they are capable of bonding into long-term relationships with a single partner for up to twenty years. (Most species that mate usually find hundreds of other mates to spread their gene pool.) They'll share the same burrow, coordinate their activities, and keep a watchful eye on their eggs together. In other cases, the female looks after the eggs while the males goes on to hunt for the both of them. Sounds like they can hold a better relationship than most people can in their lifetime.
But the problem is, 99% of crustaceans don't do 3/4s of the things that the Mantis Shrimp can/will do. While they can wait for their prey to simply float down to their coves like their crustacean kin, they can/will hunt, chase, and destroy any prey they deem delicious.
Either that or they'll come up with some elaborate dance to convince you to insert yourself into it's mouth.
Did You Know: Mantis Shrimps are not "shrimp" or praying mantis. Their name is only derived from the fact that the creature closely resembles both of the species, nothing more.