Maelstra is a Dark Faerie who appeared in the collectible card, Maelstra The Dark Faerie. Not much is known about this faerie. Her only appearance was in a collectible card, so it is hard to determine if Maelstra exists in the real Neopia.
Her description in her collectible card was:
"Lying in wait to tempt those weak of heart, the power granted by these evil imps is great, but at a price."