The blue-ringed octopus is a tiny cephalopod that packs a lethal punch. It lives in the Pacific from Japan to Australia, usually between rocks in a tidepool, and can be as small as a quarter up to 6 inches in diameter. It only displays its rings when disturbed. That is also when it bites. The bites are generally painless, characterized by some paleness around the bite and possibly a blood blister. Once the neurotoxins set in, the victim experiences shortness of breath, muscle spasms, and occasionally vomiting. If treatment is not sought fast enough, the victim may eventually die of paralysis.