“The greater blue-ringed octopus is one of several species of blue-ringed octopuses. All are thought to be venomous and for their size, they are the most deadly of all cephalopods. It is said that the venom of this octopus could kill 26 adults in just a few minutes. There is no antivenom for treatment. Fortunately, these octopuses do not attack humans. Injury typically occurs when a blue-ringed octopus is stepped on or picked up.” (Source)