Darna is a Philippine comic book heroine created by Mars Ravelo in the mid 1950's. She has an uncanny resemblance to Wonder Woman.
Darna's alter ego is Narda, a cripple. She can transform into Darna by swallowing a white stone (which came from outer space) and shouting "Darna!". To transform back into Narda, she had to shout "Narda!" and spit out the stone. Accompanied by her younger brother, Ding, they would fly across the sky in search of evil.
Her first ever nemesis is Valentina, a snake goddess who resembles Medusa. Most of Darna's enemies, are mythological creatures (both foreign and local). They range from vampires, giants to human female leeches (!).
Darna's stories were serialized in Pilipino Komiks (aside from Darna, this publication had around four to five other stories).
She doesn't really have any weaknesses to speak of, except of course the Heimlich Maneuver.
A more comprehensive background on Darna can be found at http://www.geocities.com/darnasuperheroine