Actually, at the tail end of 4e, before Essential, WOTC experiemented with publishing paperback 32 pages source books dedicated to races. They published one for Tiefling and one for Dragonborn. Each one had pages of lore and backstory, help with your character’s personality and background, dedicated Paragon Paths, an Epic Destiny, as well as feats. I have the Tiefling one, it's pretty nifty.
Player's Handbook Races: Dragonborn (4e) - Proud and Honorable Warriors If you want to play the ultimate dragonborn hero, this book is for you. This DUNGEONS &
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Player's Handbook Races: Tieflings (4e) - It's Good to Be Bad Tieflings survived brutal wars and fiendish pacts to become what they are today: sinister scions of
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