This card most obvious target might be our friend Beregond (or Beregond), but in general there are so many possible good targets, especially across the table in a Fellowship with lots of Gondor heroes/allies (Boromir, Denethor and Denethor, Defender of Rammas, Knight of the White Tower and so on)) that I always find a good use for it.
Behind Strong Walls
Action: Ready a defending Gondor character. That character gets +1 until the end of the phase.
Heirs of Númenor #8. Tactics.
I find this card absolutely great. Just 1 resource to defend a second attack with the stat boost for both attacks. You can even save it until after the shadow effect has resolved if you're hoping to hold it but need to save someone at the last second. Been having great success with this in my combat Gondor deck.