https://www.livescience.com/55478-octopus-facts.html
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An octopus has three hearts. The largest heart is called the systemic heart, which is in the middle of an octopus's body. The systemic heart pumps blood all around the body except for the two gills, which each have their own smaller heart called a branchial heart, or gill heart...
All octopuses are venomous. Blue-ringed octopuses are among the most toxic animals on Earth, and have a neurotoxin that can kill humans...
The largest known octopus is the giant Pacific octopus, which weighs as much as 600 pounds (270 kilograms) and grows as long as 30 feet (9 meters) across, according to the Marine Conservation Society. That's as long as a bus! .."
