Thematically this deck is two Gondorian scouts convince Grimbeorn and Radagast and his army of eagles to join their endeavors. Obviously enemies cause little trouble here because Grimbeorn is a fricking beast, and all the eagles build up to an unstoppable level typically by mid game. Add Bears to that and even by early game you will be able to handle most enemies.
Mono tactics of course struggles with locations, card draw and questing. To answer that you have the Meneldor and Meneldor's Flight and Born Aloft combo to spam progress on locations in the staging area. Beorning Guardians do double duty killing enemies and adding more progress, and you can retrieve them with Beorning Skin-changer and of course Gwaihir allows you to bring important eagles back.
Resources are no problem, which is important in a deck with so many expensive allies. First, Hirgon helps (if you quest), then Mablung helps more since you need to be engaging enemies with all the muscle you will have, plus Radagast helps play and heal all your creatures (practically all your allies), and finally Horn of Gondor cranks out a fee extra resources when you need them.
You will think you're playing a Leadership deck, and you'll need it to play Gandalf which I use for card draw (along with Legolas) or threat mitigation, along with Secret Vigil. So the most important thing to do is get questing help out asap, so Hirgon can get his discount and you can start dropping tons of eagles and beornings on the board. Put excess resources and Horn of Gondor on Grimbeorn the Old so he can use his crazy smack-back ability, and dont be afraid to use your Giant Bear ability to munch key enemies early because you will be able to retrieve them later with Beorning Skin-changer for dirt cheap. As usual for an eagle deck Eagles of the Misty Mountains gets super strong by mid game, at which point adding Support of the Eagles to Grimbeorn the Old makes him a nearly invincible monster smashing machine. I hope you have fun with this one. --Mad Morderan