Thought I'd share an Ent deck that I've had a ton of success with so far in it's short life. It was partially inspired by Seastan (the good harvest/steward of gondor combo). So far I have played and defeated:

The prancy pony

Massing at osgiliath

Siege of cair andros

Journey down the anduin

Those are the only four quest I've played so far with it but it absolutely crushed massing at osgiliath (something I've had a hard time with in the past).

I know people say treebeard doesn't synergize with ents but I disagree. Having an ent out turn one helps use ent moot, ent draught, etc right away. He also helps out booming ents as he is almost always damaged.

Good harvest, besides helping in paying for steward is phenomenal in getting out a wellinghall preserver turn one.

Finally I love the theme of the two hobbits with treebeard. I've had a ton of fun with this deck, so here it is:

Treebeard

Merry (tactics)

Pippin (lore)

Allies:

3x gandalf (core)

3x wandering ent

3x booming ent

3x wellinghall preserver

2x quick beam

2x derndingle warrior

1x skinbark

1x beechbone

1x elrond

Events:

3x feint

3x ent moot

3x peace and thought

3x good harvest

3x daeron's runes

3x boomed and trumpeted

1x deep knowledge

Attachments:

3x ent draught

3x steward of gondor

2x fast hitch

1x burning brand

1x self preservation

1x song of battle

Side quests:

1x scout ahead

Stoled.