Long gone is the frivolous, shallow girl of season one, who wanted nothing more than to marry well and live a comfortable life (which, considering that Sansa was barely even a teenager in season one, wasn't that unreasonable of a life goal). While Sansa began her journey as a timid, naive child, after apprenticing under the likes of Cersei Lannister, Petyr Baelish, and Olenna Tyrell, the current Lady of Winterfell has grown into possibly the smartest and most cunning player left in the game. Sansa may not be a fighter, but her wits are sharper than Valyrian steel, and we don't expect that anyone — undead or otherwise — will be savvy enough to get the best of her.