Fili and Kili are crazy good in a deck running the Fellowship contract. As long as you have one of the brothers and a copy of A Very Good Tale, you can play him, go grab the other, then exhaust both with AVGT to potentially drop two more allies. The result? Four unique allies toward your goal of 9 at the cost of 3 only resources! Of course, they are also integral pieces in a Dwarf swarm that wants to get to 5 as soon as possible.

The biggest downside is that Fili (and Kili) are at their most exciting and powerful when they enter play. Afterwards, the stats-to-cost ratio is actually below average (though Dáin Ironfoot and Hardy Leadership can help with that). In sum, it's great fun to bring them into play, and then they provide only decent contributions to your board state afterwards.

Beorn is certainly a unique hero, and one of my favorites. One interesting thing about him is that he has stats that total WAY more than his starting threat (he should be at 16!!!) so all you Glorfindel fans should appreciate this. I think he is an amazingly powerful hero, and one that can be so SO clutch in the early game, especially for quests that hit you hard early on. I think Beorn's value also goes up in multiplayer, where he can handle multiple attacks early on, and then kill an enemy without needing any weapons or attack boosts. His favorite enemies to kill are obviously goblins, because he can handle their swarms and swat then down. I love the thought of Beorn, a giant bear, charging into battle, taking on swarms of enemies and surviving, clawing them to death!!! I think the artwork and the text on this hero is just perfect. Yes, he has drawbacks, and is a different sort of defender that Beregond, but one that is, in my opinion, more fun to play. Sadly, with many enemies having bigger and bigger attacks stats (4's and 5's) Beorn sed less and less use, which breaks my heart, because he is one of my favorite tactics heroes to play. But for some quests (The Battle of 5 armies comes to mind--very thematically appropriate!!) Beorn just shines.

This guy can be absolutely clutch in a Silvan build, particularly when paired up with Thranduil and enjoying the boost from Celeborn. The trick is waiting for the strategic moment, which is made all the easier by Thranduil's combat action. I've lost track of the number of times that multiple enemies have bounced off of Greenwood Defender, allowing the other Silvans to stay ready to counter-attack and get the board under control. Even if he falls to enemy attacks, oftentimes the ability to block a few smaller enemies first is invaluable.

If you aren't running Thranduil, you can always pop him in with Sneak Attack during the combat phase (less cool than Gandalf, but potentially more effective under the right circumstances). If he lives through his first round, he can soak up archery quite nicely (especially for a Silvan) and then be healed up by Silvan Tracker to repeat the process. The only thing he's really missing is sentinel, which would elevate him to top-tier in my opinion.

Great card for Silvans that has almost completely replaced Defender of the Naith for me.

I agree (he's much better than defender of the faith, who was never really great). silvan decks have always struggled with defending for me, especially if you're not running thranduil, but this guy is a beast —
#naith —
Yeah, the two possible advantages of the Defender of the Naith are neutral sphere (completely negated by using Thranduil's ability) and sentinel (which I would happily trade for the extra health of the Greenwood Defender). —

This card is similar to Sneak Attack, albeit in Tactics and with some specific requirements. Using the new ALEP cards, you can build a Radagast/Alagos/Faunith deck with this and Sneak Attack and get Ally Gandalf's effect nine times!

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Does anyone know what would happen if you used this to summon ally Gandalf during the resource/planning phase action windows, and then played Sword-thain on him? Would he persist on board as a hero? If so I want to build some shennanigans with this... —
To specify, I mean the OHUH Gandalf, not core gandalf —
Unfortunately, Sword-thain cannot go on Gandalf because he does not belong to any sphere, however, your trick does work with someone like Meneldor. —

I've found myself including Lórien Guide more often in Silvan questing decks for his/her 2 more than anything else. Silvans are notoriously weak to direct damage, particularly when treacheries target all questing characters (i.e. Blocking Wargs), and so having a board state that will not be completely wiped out by a nasty treachery is quite nice. The cost of 3 is slightly high (as many of the previous reviewers have pointed out), but I can see how this ally would be almost too strong at a cost of 2. Besides, Silvans have many ways to mitigate this (O Lórien!, The Tree People), and so while not ideal, the cost is not prohibitive.

Lórien Guide is not an auto-include by any stretch, but s/he does have a usage even before the bonus ability is taken into account.