OK, so I just played my first few games and, for the most part, I'm really enjoying it so far.

However, I just played a solo game doing the "Don't Leave the Path" quest (the 3rd card of Passage Through Mirkwood), and Ungoliant's Spawn (the card I had to defeat) was the very last card in the deck and it was unfortunately drawn as a shadow card. I gave up at that point since (as I understand the rules) he would have been shuffled with the discards into a new encounter deck and I would have had to potentially go through the entire deck again.

I just wanted to check I played correctly? If so it seems like a massive design flaw in this particular quest. I'm guessing there are other similar quests where you need to reveal a certain card and the same thing can occur. Please tell me I'm doing it wrong because this sort of thing can really suck the fun out of games.

When you advance to stage 3 it instructs each player to search the deck for a spider enemy. At that point you simply search for the Ungoliant spawn. Technically you didn't play wrong (as in you didn't break any rules) but you missed an easy fix.

"Don't Leave the Path" instructs you to search for 1 Spider card and add to add it to the staging area. This card should be Ungoliant's Spawn, of course, otherwise you're facing the problem you're mentioning here.

Aaaaaaaahhhhhhhhhhh, yeah that's really obvious now you've told me lol. I searched until I found the first spider in the deck - should have read it more carefully. Thank you both

And just so you know, there are no more quests in the game that require you to kill a certain enemy that isn't specifically brought out by a quest card effect.