I finished up running Hoard of the Dragon Queen about eight-ish months ago. I’m very much late to the “it was okay” party, but that’s sort of how I do, so let’s get rolling.
Hoard of the Dragon Queen has a very strong start and a pretty strong finish. The opening chapter is a raid on a farming town by the Dragon Cult, primary villains of the adventure path, including an actual goddamn adult blue dragon. The whole thing is a fighting retreat, trying to save people from the Cult and evacuate, rather than any hope of actually winning. This is a compelling intro that serves to make the antagonists threatening and intimidating without threatening to wipe the party.
It does, however, threaten to wipe the party on top of that. Level 1 characters will have a Hell of a time getting through all the content in Greenest. I think the idea might be that you’re supposed to skip some of it, but that seems like a waste. It’s not like I’m very likely to run this campaign again and need to reuse content. I’ve heard it advised that you can have characters come to Hoard of the Dragon Queen directly off of Lost Mines of Phandelver, and while level five is a bit much for Greenest in Flames, it would still probably go better than trying to run it as level one. Better to have your players feel like they’re more badass than any one thing the Dragon Cult has to throw at them except 1) for that dragon and 2) the Dragon Cult has lots of kobolds and action economy is a pretty decisive factor in 5e, as opposed to having them constantly dropping and getting back up and maybe some of them being killed outright at some point if they’re heroic enough to decide they don’t want to leave any of the villagers to their fate.
After saving Greenest, there is a reasonably compelling pursuit of the Dragon Cult to their hideout, you snoop around, most of the Cult moves out, you clear a dungeon full of those left behind. It all works, and the opening has given it enough momentum to keep it engaging. The one-page dungeon in chapter three is, y’know, a one-page dungeon, moderately interesting but only moderately. Coming as it does at the climax of the players’ struggle with the Dragon Cult in the Greenfields, though, it works. It can borrow dramatic tension from the great setup.
The problem is that there isn’t another really good moment like this until towards the end. The trip up the road from Baldur’s Gate to Waterdeep and the hike through the swamp are a decent introduction to the Sword Coast for players new to the setting, and what with 5e’s sudden, podcast-fed popularity that’s pretty handy on its own, but it struggles to be even mildly interesting. The encounters on the way are each individually good, but the framing story is railroad-y and completing encounters doesn’t feel like you’re getting any closer to your goal. You’re following the Dragon Cult back to their lair, but disguising yourself as guards in the caravan they’ve joined (themselves disguised as merchants) is the only option given for doing so. Interrogate captured cultists? Have a Ranger or other woodsy type track the caravan? Pretend to be pro-Tiamat and infiltrate the cult? Disguising yourselves as caravan guards isn’t exactly the most straightforward or obvious plans, so you can definitely feel the rails when you’re driven into it. Castle Naerytar doesn’t have the momentum that the Cult’s hatchery did, even though it is a bigger and more interesting dungeon with competing factions, good enemy variety, and a sensible but complex design. It’s a good dungeon, but unlike the hatchery it is enervated rather than enlivened by what came before it.
The finale is pretty good. Another fairly well-designed dungeon, this one a fantastic location with some great treasure. The hoard itself is actually pretty disappointing, but the flying castle is pretty awesome. The means of acquiring control of it are a bit hard to figure out, but Kobold Press released another adventure about attempting to retrieve it from where it crashes if you don’t end up making friends with the ghost who runs it. Even taking Hoard of the Dragon Queen by itself, it makes a pretty spectacular climactic location.
Each individual element of Hoard of the Dragon Queen is great. Even the slump in the middle still consists of lots of individually good encounters topped off with an individually good dungeon. Run as an adventure whose goal is to get a caravan from point A to point B in exchange for mad dosh, it’d be fine. The reason why it comes off so dull and even frustrating is because there is a constant sense of “aren’t we supposed to be saving the world?” hanging over everything. You could rip that chapter out and use it on its own and be fine, though, or the first three chapters as a standalone “local bad guys raid mid-sized town” kind of plot, or take the climax and drop some other villain in there if you feel like giving your players a flying castle. Each individual element works, so to the extent that Hoard is flawed (besides the fact that each individual element is still imperfect), it’s that the different pieces don’t fit together very well.