https://phys.org/news/2018-07-cooler-ocean-predator-sharks-mantis.html

And it accomplishes this feat without claws. Instead, it's armed with a powerful pair of what scientists call "raptorial appendages" that end in a brutal hammer or a series of vicious, pointed spines. These prey-catching arms look somewhat like the front legs of a praying mantis, which gives these creatures their name – mantis shrimps.

They're crustaceans – the group of hard-shelled animals that includes crabs, lobsters and shrimps. The strength of the mantis shrimps' raptorial arms together with their amazing eyes make them perfect predators.