Over a thousand years ago, the scattered elven communities began to hide themselves from their boisterous human neighbors. The last great elven city, Atoriel, disappeared without a trace, until it was discovered years later to have been teleported piece by piece to an island. The elves on the island kept up peaceful trade with humankind until one day the entire island disappeared, nowhere to be found.
The ancient elves were very skilled magic users, sometimes spending much of their lives on the fringe of the material plane, a dimensional margin of sorts known as the feywild. Many suspect that’s where they are now, but no one knows for sure.
Elves are not currently a playable race. If you seriously want dex, wis, and encounter reroll, I’m thinking of giving those qualities to the tails-side lizardmen. Their writeup is pending.