A player of mine has recently asked me to double check a ruling I made:
He had asked if Thalia's Lancers could fetch Westvale Abbey since it's backside is Legendary. I ruled that no he could not based on 711.4a While a double-faced card is outside the game, in a zone other than the battlefield, or on the battlefield with its front face up, it has only the characteristics of its front face. The plkayer at another event had a higher level judge tell him that he could in fact fetch the Abbey with the Lancers.
I want to double check for his sake and my own which ruling is correct.

Hello,

Unless the double faced cards is on the battlefield and transformed, you ignore the back side of the card. The Abbey is just a land: the back side is a legendary creature, but we ignore the back side since it's not on the battlefield and transformed. Since the Abbey is not a legendary card, you cannot find it with the Lancer's triggered ability.

Nathan Long
Magic Rules NetRep