i.e. "A wizard did it."
A fairly straightforward deck, focused on hero Gandalf. Inevitably, as the deck uses Glorfindel, you should mulligan for Light of Valinor. Ideally you want to find a copy of Bilbo Baggins quickly as well, to locate the Wizard Pipe. A Burning Brand is to played from the deck onto Gandalf (as his ability gives him a icon). Hidden Cache is to be used with Expert Treasure-hunter, discarding it to gain resources then returning it to hand, followed by returning it to the deck on the next round with the Pipe (unless it's more important to use the Pipe for something else). Resources from the Caches should always be placed on Glorfindel. The 3 copies of Beorn are not intended to be played, instead serving as "ammo" when playing Flame of Anor (an earlier version of the deck actually used Core Gandalf, though I'm not sure it would be allowed, simply for humour value). Unless the quest you're playing has some very specific requirements, all copies of Unexpected Courage should be attached to Gandalf. The one copy of Word of Command may go unused, but is very helpful if Gandalf has a spare action and Light of Valinor hasn't shown up yet.
This deck works fine for both solo and multiplayer, though if played multiplayer the Unexpected Courages may be valuable on heroes in other decks. In multiplayer, you should also swap a copy or two of Shadowfax in from the sideboard (I've most commonly found myself replacing Arwen Undómiel, due to somebody using the hero version, with Elrond a possibility for the same reason). In solo, the extra action is unneccessary, 3 copies of Unexpected Courage suffice, and ranged and sentinel are pointless, but neither part is true in multiplayer. Narya is more of an afterthought: Gandalf doesn't need the Leadership icon, and the deck isn't remotely focused on allies, but in multiplayer there may be some good targets.