1. Box Jellyfish
You have virtually no chance to survive the venomous sting, unless treated immediately. After a sting, vinegar should be applied for a minimum of 30 seconds. Vinegar has acetic acid, which disables the box jelly's nematocysts that have not yet discharged into the bloodstream (though it will not alleviate the pain). Wearing panty hose while swimming is also a good prevention measure since it can prevent jellies from being able to harm your legs.
Jelly box can be found in the waters around Asia and Australia.
2. King Cobra
It's venom is not as toxic as other venomous snakes, but King Cobra is capable of injecting 5 times more venom than black mamba and can result in mortality up to 5 times faster than that of the black mamba. It is quite widespread, ranging across South and South-east Asia, living in dense highland forests.
3. Marbled Cone Snail
Symptoms of a cone snail sting can start immediately or can be delayed in onset for days. It results in intense pain, swelling, numbness and tingling. Severe cases involve muscle paralysis, vision changes and breathing failure. There is no antivenom. However, only about 30 human deaths have been recorded from cone snail envenomation.
4. Blue-Ringed Octopus
Painless bite may seem harmless, but the deadly neurotoxins begin working immediately resulting in muscular weakness, numbness, followed by a cessation and breathing and ultimately death.
They can be found in tide pools in the Pacific Ocean, from Japan to Australia.
5. Death Stalker Scorpion
Death stalker scorpions are spread in North Africa and Middle East.
6. Stone Fish
Stonefish stores its toxins in gruesome-looking spines that are designed to hurt would-be predators.
Stonefish mostly live above the tropic of Capricorn, often found in the shallow tropical marine waters of the Pacific and Indian oceans, ranging from the Red Sea to the Queensland Great Barrier Reef.
7. The Brazilian wandering spider
This spider is believed to have the most potent neurotoxic venom of any living spider. Only 0.006mg (0.00000021oz) is sufficient to kill a mouse. They are also so dangerous because of their wandering nature. They often hide during daytime in highly populated areas inside houses, clothes, boots, and cars.
Its venomous bite causes not only intense pain, the venom of the spider can also cause priapism - uncomfortable erections lasting for many hours that lead to impotence.
8. Inland Taipan
9. Poison Dart Frog
10. Puffer Fish
This puffy fish produce rapid and violent death..Puffers poisoning causes deadening of the tongue and lips, dizziness, vomiting, rapid heart rate, difficulty breathing, and muscle paralysis. Victims die from suffocation as diaphragm muscles are paralyzed. Most of the victims die after four to 24 hours. There is no known antidote, Most deaths from fugu happen when untrained people catch and prepare the fish.
Statistics show that there were 20 to 44 incidents of fugu poisoning per year between 1996 and 2006 in all of Japan and up to six incidents per year led to death. Since Fugus poison can cause near instantaneous death, only licensed chefs are allowed to prepare it.