Medusa Dread
No one likes dealing with a medusa dread, even other medusa. This abomination, just before being born, burrows deeper into its mother (which is a normal medusa), and begins feasting. Not until the mother medusa dies in the next few hours does the medusa dread eat its way out.
Medusa dread are rare, and are thought to be myth by most. Making them even more rare is the fact that if the father is present when it is born, he kills it. Unlike its parents, it will eat anything, even other medusa.
Medusa Dread Tactics
The medusa dread is not smart enough to make bows, but it can fashion spears and javelins. It prefers to live in caves or dungeons where others cannot get decent range on it. If it thinks it can win a fight without using its petrifying gaze, it will do so (so as to eat the prey later). 
Otherwise, it prefers to use its javelins at first, and then move in for close combat to get the most out of its reactionary petrifying attack.
Medusa Dread Lore
A character knows the following information with a successful Nature check, in addition to what is found in the Monster Manual.
DC 15: A medusa dread is said to be the body of a person, and the tail of a snake (and rather large), though that is supposedly a myth.
DC 20: Medusa dread are not smart enough to carry out aspirations of wealth and power. If they ever gain it, it doesn’t last long.
DC 25: All other medusa hate the medusa dread, and will either send small armies of underlings after it, or gang up on it with other medusa. It’s gaze attack is more potent than smaller medusa, and it can use it more often. Even after a killing blow has landed, the medusa dread can still get off one last petrifying attack on its killer.
Chris Stevens
In Chris's opinion, the very best vices are dirt bikes, rock music, and gaming, while the very best medicine is fatherhood. If he could just learn to balance them all, he'd live forever. He's much more creative than intelligent, often wakes up belligerent, and ponders many things insignificant. Lastly, in an effort to transform his well-fed body, P90X, Roller Blades, and Food are all laughing at him. And the pain continues.
Now that is the medusa I have always thought of.