Blue Octopus
These beautiful creatures are found in the waters between Japan and Australia, their rings change color instantly when they feel threatened. With a lifespan of two years, they do everything to survive for the entirety of it. They are super small being between 12 to 20 centimeters in size. Their venom contains the powerful neurotoxin tetrodotoxin which leads to heart failure, respiratory arrest, and nausea. If truly severe people can end up paralyzed, blind, and dead. The rings turn blue when the octopus feels targeted or threatened this is a sign to steer clear.
Blue Octopus
Stonefish
Extremely hard to find and see, with their impeccable camouflage, Stonefish are the most venomous of the sea. They look just like rocks. Their dorsal fins stand tall ready to inject any wondering foot that may just happen to stand on the seabed below. Their venom contains neurotoxins and the more one stands on it the more venom that is released. They have another defense mechanism that has only recently been found, a switchblade on their face. Without antivenom, a human can die within the hour.
Stonefish