The Blanket Octopus (Tremoctopus spp.) is one of the ocean's most visually dramatic and biologically extreme cephalopods. Females are enormous compared to males, trailing a large, flowing web of skin that can be unfurled like a cape when threatened. This membrane makes the animal appear far larger and more intimidating to predators. Remarkably, Blanket Octopuses have been observed ripping off tentacles from venomous siphonophores and wielding them as defensive weapons. They live entirely in the open ocean, drifting and swimming rather than hiding. Their alien appearance and rare sightings make them a legend among marine biologists.