Pandora is regarded as the first-ever human in Greek Mythology. She is often known for her box which released all the known evils of the world including disease and death.
Europa was one of Zeus/Jupiter's many affairs. The divinity appears to her in the form of a white bull and carries her off far from her home. She was one of many with a similar story.
Theseus' most popular achievements were navigating the labyrinth with Ariadne's help, defeating the minotaur, and escaping the underworld with Heracles' help.
Likely the most popular hero in all of Mythology, known for killing the Nemean Lion and the Hydra, completing the "Labours of Hercules", and being the son of Zeus.
Perseus, another son of Zeus, is known for killing Medusa, the gorgon with snakes in her hair that turned her enemies to stone with a single look.