J'onn Jonn'z, Last of the Green Martians
The Martians were an ancient species living on their arid red world. They possessed a genetic memory they could recall the lives of their ancestors in incredible detail. At their peak millennia ago they built a towering civilization that would rival anything on modern Earth. Today the Martians are an extinct people, blasted from the surface of their world. A terrible civil war burned away atmosphere of Mars and along with it all evidence of life.
Millennia later the Radovednost probe landed, grabbed a soil sample and launched the sample back to Earth. Examining the sample scientists found what they thought impossible, evidence of life, a damaged cellular structure. Using science right out of Jurassic Park the cells were cloned. Dangerously, foolishly, a military science team had created a living Martian.
J’onn Jonn’z was confused, terrified and had every memory of his ancestors in his mind. He could remember the horrors of civil war, his family, his ancestors but he couldn’t remember how he came to where he was. Terrified the Martian ran, using his immense strength and his ability to shapeshift he fled the facility. Taking refuge in cities all over the United States J’onn hid his nature by taking the form of the homeless that so were so easily ignored by society. Among those without true homes he found kindred spirits, the lost, the scared, the forgotten, the alone.
He protected those homeless people that he found. J’onn moved from city to city finally stopping in Chicago. He shadowed police detective John Jones after the man was the only one willing to look into murder of a dozen homelss people. For months the Martian watched the huma, occasionally interacting with the man in the guise of a different homeless person each time. J’onn was drawn to the the detective, he was as lost as the Martian and he had a sense of right and wrong that J’onn respected.
J’onn finally revealed himself to the human he’d followed for months. The detective was surprised but not scared. The two became fast friends, and J’onn picked up his human friend’s love of the Oreo cookie. During his time with Jones J’onn learned the fate of his world, it was dead and his people were gone.
John Jones died at a convenience store, killed in by during a theft when he was buying J’onn a bag of cookies. The Martian found his friend bleeding out, and the detective made him promise to keep his sense of justice. J’onn took the Detective’s form, and has kept his promise to his friend by fighting injustice every day since as the Martian Manhunter.