Hydra: The Water Snake
Appearance
A giant snake with many serpentine heads
Weakness
Needed to have at least one head to be immortal
Special Powers
If you cut off one head, two more would grow back. It could spit a poisonous venom, it had poisonous breath and even its scent was deadly.
Myth
Heracles was tasked with killing the hydra. For this feat, he brought along his nephew, Iolaus. Cleverly, they covered their noses mouths to protect themselves from the deadly fumes of the beast. Heracles cut off one of the monster's heads, but then two head grew back and took its place. He cut off two more heads, and four more grew back. Iolaus figured out he could use a burning torch to seal the neck stumps when Heracles cut off one of the heads so they couldn’t grow back. Heracles put an end to the hydra when he cut off its main head and buried it under a large rock.