I don't actually own quite all the cards needed to make this deck but I thought the idea was fun enough to be worth sharing.
On a basic level, the idea here is to use Leadership hero Faramir to get around the primary weakness of ents (i.e. they come in tapped). While you're at it you can swing some extra resources on Mablung. Nearly half the deck has the ent trait so each ent moot has the potential to net massive card draw.
The intent of this deck, is that it's to give a nasty surprise to scenarios that like to have enemies engage you at odd times. It does not have shadow card or treachery cancel and in general it's willpower isn't incredibly high but what it does have is a ton of ways to get extra high value activations. Both Faramir or Mablung activate once per phase so each enemy jumping you during questing or combat can quickly become an extra buck and an extra ent to work with. Obviously, avoid any quest that punishes having lots of allies.
In addition to Faramir, the deck runs ever Boomed and Trumpeted and Ever Vigilant to get extra uses out ents (or Gandalf). Treebeard's resources can also be well spent on this if you don't need them to build your int horde.
Gríma may be better than Denethor if you're playing solo or with allies who can take a bit of doom. He gives better questing and you don't really need to block with your heroes in this deck generally.