Called "sea locusts" by ancient Assyrians, "prawn killers" in Australia, and now sometimes referred to as "thumb splitters" - because of the animal's ability to inflict painful gashes if handled incautiously - mantis shrimps have powerful claws that are used to attack and kill prey by spearing, stunning, or dismembering.

https://www.youtube.com/watch?v=F5FEj9U-CJM