Blade: Both parents died when he was a baby and he and his brother were adopted by ninjas, they both trained for days until one day Knife killed their sensai and ran off, Blade swore to kill Knife and avenge his sensai.

Night: Night was a mercenary, he and a long time friend were given a special job at an experimentation facility, they were forced into torture to see how long they can take damage and were experimented on, each of them died but Night was messed up so much he came back to life and killed all the scientists, his friend's body was never found. (Duh, I wonder if this will be important in the story, hint hint wink wink)

Bang: Bang decided at the age of eight he wanted to be a bounty hunter, his father only asked "Why?".

Dark: Dark became king after the death of Black-Doom. (You know, main bad guy from Shadow the hedgehog) He has a third eye like his father and is the key to a profecey about how when his third eye opens at the age of twenty, he will destroy all none dark-creatures and rule the universe. He has had a pretty f$%#ed up life, he had a girlfriend who was eaten alive by zombies in front of him after a car fell on him, his best friend was murdered by someone trying to assassinate him, and he has a bunch of palidens trying to kill him.

Azazel: How the hell should I know his story?! I didn't make him up moron!