Dangerous Jellyfish:

The Box Jelly, [aka Sea Wasp or Chironex Fleckeri; pictured above left and resulting scars right] - and 20 near relatives are found off the shores of Northern Australia, PNG, Malaysia, Indonesia, the Philippines, Thailand and Vietnam. This marine animal has a boxy bell head the size of a basket ball, 4 parallel brains [one on each corner], 24 eyes and 60 arseholes! [says Dan Nilsson, a vision expert from the University of Lund in Sweden]. Then there are 5,000 deadly stinging cells on each of its 10- 60, two metre long tentacles.
Some researchers believe that groups of Box Jellies deliberately herd small fish and crustaceans towards the shore in order to trap them, thus bringing them into contact with humans.
New Scientist magazine in 2003 revealed that Box jellies are not 'dim-witted ocean drifters' but 'fast, active predators that hunt and kill with incredible speed and brutality.'
This Toxic Box is responsible for at least one death a year around Australia and has killed 67 people since records began in 1883, though the total is misleading since many deaths attributed to heart attacks or drowning could have been caused by toxic jellies.
Problem shores are usually signposted, and this is one serious bubblepack to be avoided at all costs - the most poisonous creature in the world.