Dragonborn: Are stupid and for munchkins only. They simply do not exist in this world.
Elves: The elves departed the Old Realm, and the Known World it seems, some thousand years ago, taking with them their personal possessions, much of their art, and virtually all their records. Their lands, collectively called Ahris, were quickly reclaimed by nature once their magic was gone and are now places of wonder, myth, and danger. No elves have been seen in the Known Lands for centuries, although rumors persist that some stayed behind or that there are those who’ve returned for some reason or another to their former homes. The most reliable histories have them departing by Fahrenkoor River or Elgendahr River, heading toward the distant open seas – far outside of the Old Realm.
Tieflings: They don’t exist in the Known World and are only indicated in some histories and legends.