Saba

In ancient Irish legend, the wife of Finn Mac Cummal and mother of Oisin. Finn captured her in the form of a fawn while hunting, but noticing that his hounds would not hurt her, he gave her shelter. The next morning he found her transformed into a beautiful woman. She told him than an enchanter had compelled her to take the shape of a fawn, but that her original form would be restored when she reached Dun Allen, where she had just spent the night. Finn made her his wife and ceased for a while from battle and hunting.

Hearing one day that the Northmen's warships were in the Bay of Dublin, he mustered his men and went to fight them. He returned victorious, but found Saba gone. The enchanter, taking advantage of Finn's absence, had appeared to her in the likeness of Finn with his hounds and lured her from the dun. Away from the dun, she became a fawn again.