Fiend of the Shadows

[Druknal]

If a {Fiend of the Shadows} were to hit my opponent, then be killed before I cast the exiled card. Would I be able to play the card exiled before the death if I was to play it again? Or does the ability essentially reset and the card is exiled forever less it could be effected by {Runic Repetition} or something of the sort?

[Poof]

You may play the card as long as it remains exiled.

[Druknal]

Aigh. Wasn't sure if it was conditional to the card being alive. Although aware it would of stated "while on the battlefield" or something.