In Japan, staying alive after you eat a toxic pufferfish is a common goal.
In fact, here, they are considered a delicacy...a potentially lethal one.
Their skin and liver contain tetrodotoxin, a lethal paralyzing agent.
One bad slice of pufferfish sashimi can kill a grown man.
Some pufferfish have prickly spikes that lay flat against their skin...until they're alarmed.
It gulps down water into its elastic stomach, bloating its body into an instant beach ball.
Oddball defenses are good in theory, but what about in practice?
Let's find out, in an underwater battle royale.
In this corner, the reigning featherweight champion, H.R. Puff-n-Stuff.
In this corner, the double-jawed death dealer, Mr. Moray Eel.
The eel strikes first.
But the pufferfish moves up a weight class.
The eel can't maintain its grip, and the pufferfish lurches away.
Oddly enough, the pufferfish saved not only its own life, but the eel's as well.
Had the eel managed to make a meal out of the toxic puffer, it would have been its last.