Flag of Hydra, Moon of Pluto
The flag Hydra is based upon the legendary Hydra that Hercules had to slay as one of his twelve labors.
The flag of Pluto's Moon Hydra has four colours: navy blue, green, purple, and black. It is a vertical tri-bar with wide Canadian Pale. In the center is a charge that is a stylized version of a Hydra with nine heads. In the purple bar is the classical symbol for Pluto, and in the green bar is a black crescent moon.
Typical image of a Hydra
The Hydra has been key note in bad monsters. From Nintendo's Zelda, Hercules, Transfomers, and various forms of art. The Hydra is negatively portrayed as the beast that must be slain by some hero.