If you play with ALEP cards, then you can have Box of Earth to make your Cloak of Lórien on Elrond almost as good as Gondorian Shield on Denethor or Beregond. Also, as previously mentioned, this is the only lore card with reliable defense. It also goes nicely alongside A Burning Brand.
In addition to the Thorongil options already mentioned, I like Fighting Merry in a Bond of Friendship deck to have Fast Hitch and gain the threat reduction from Hiding Merry. Denethor to Denethor with plenty of Unexpected Courage is always nice to make sure you use up all your activations when there wasn't much blocking in a given round. (As compared to nearly every other blocking hero, whose extra activations go to waste.)
Most of what needs to be said has already been said here, but I wanted to add two more targets: Prince Imrahil and Haleth. I'd also note that this attachment is more likely to find a juicy target when you're playing multiplayer, especially 4P.
A really good ally with a high-risk, high-reward text. And allies with two Willpower for two resources are always great, even if most of them have Spirit as a home.
For its Action, it is specially good in a deck that feeds its discard pile, like Noldor, Caldara, or any deck with key cards that should not be lost, like Council of the Wise. For the passive ability, I understand it thematically, losing the game if Frodo dies - for which it's nice to have two hit points! But I don't understand the thematic excuse for his action. Is Frodo now a Necromancer, resurrecting dead allies? Is he delving into the ancient writings of Minas Tirith like Gandalf? Why can he retrieve cards from the discard pile?
Anyway, a great card that even allows you to use the Spi ally Sam Gamgee. And you can always nullify the risk by returning him to your hand after using his Action with effects like Lily Cotton - even if it doesn't allow you to use his action again.
I like his stats, he can be used at questing or defending. But I don´t see many options to discards allys from play. Maybe someone can help.
At first glance I wanted to combine him with Eowyn and Theoden in a mono spirit deck.