The Last

I was once bitten, once normal, once afraid.
I was told I would be known to humans as an angels.
I was told evil supernatural creatures would call me the devil.
I was told I was to meet two men at the age of 18.
I was told they would be scared, suspicious, frighten and I was to change that.
I was told I of a legend to save human kind with only my powers and weapons.
I am Onyx Lith and I am the last shapeshifter and elemental.