We play mainly two player. First quest was tough but pretty fun.
Second quest, seemed pretty easy to us. The Goblin King seemed like a real easy pushover with just not much else happening.
But the third quest seems just absolutely BRUTAL to me. We've played it 7 or 8 times without a win. The riddle mechanics just seem very hard to have much skill with, unless you build your entire deck out of one sphere and only one or two different costs. We don't build different decks for each quest, instead choosing to build a deck that can try to make it through the whole cycle. I built a two sphere deck, Spirit/Lore (about half of each), where I had about 20 cost 2's, and about 15 cost 0's. That seems like it should've been at least decent at guessing for the riddles, but I still kept failing a TON of them because it's a crapshoot. Some you have to guess sphere, cost AND type, and many you have to guess two of the three. It's just highly random. I don't think my deck seems THAT unreasonable of something that should be able to play against this quest, but I don't think we made it to the third stage even once. Basically you fail 3 riddles and Bilbo dies, and many times you'll hit 2 or 3 riddles each turn, sometimes more because of certain treachery cards.
Just crazy.