See: Lanal Voidcaller, Elves, Heroes of Goldcrest
Lanal was once a Void Elf of great stature, but she was always hungry for more power. This power was easily obtained when she made a pact with a Fiend Lord, Shax. He however ultimately betrayed her, and crippled her severely with his torture. For this reason Lanal needed to bond with an Eidolon, just so she could walk, so she did. However she never learned the magical side of the Summoner. In the end she ended up in an anti magic prison cell, where she could not move at all. until she was rescued.