Revenge of the Kobold King was okay but not as good as it's predecessor. I agree with the below comments regarding disappointing magic items and I felt the camp and the barrows were too crowded with bad guys. Boss Teedum and his men seemed like an afterthought and I thought the adventure was a little rushed.
I did like some of the traps and ideas used in both parts, I almost wish Depnaakra had been used as the main villain instead of the undead Merlokrep. The Sting Warden had potential!
I also liked the Azlanti Chariot Beetle, I'm always excited to see new creatures.

This is a neat scenario with plenty of backstory to set the scene and perhaps spawn further adventures. A logging crew is slaughtered messily while at work deep in the forest, and the characters are hired to find out by whom and deal out some retribution. Part of the background involves a previous adventure, Crown of the Kobold King, but it doesn't matter if you haven't played it - the kobolds might be seeking revenge, but they are none too good at distinguishing between parties of adventurers! Of course, if the characters have played that adventure, it is a delightful way of reminding them that their actions have consequences...

The adventure itself involves a hike through trackless wild forest, with a fascinating array of encounters each with its own story - all adding to the alternate reality of your game world being somewhere that gets along just fine whether or not the characters are there. Once they reach the logging camp - well, 5th-level adventurers ought to have strong stomachs, they will need them as the sights to be seen are quite gruesome... and deadly! But that's not all, clues lead the party onwards (assuming they survive) to a final showdown which, apart from a bit of dungeon-crawling and a good brawl, has a lot for those who have an interest in the history of the land to discover.

With a strong backstory, lots going on and the potential for further adventure, it's surprising that it was all packed into 16 pages! As a stand-alone or as part of an ongoing sage this has plenty of potential.

Overall this is a great module, very challenging for a 5th level party with lots of undead and a few creepy critters. There are a few issues I have with the module though. First, the number of 'regulators' sent with the party is never mentioned and this can be critical in the end of the module. Second, and perhaps the most concerning is that the treasure in this module is all focused on a few high powered magic items near the end. Also, almost all of the good "martial" themed items are size small while which leave fighters a bit short changed by the end of the campaign. Finally, the barrows are cramped. The rooms are small for the number of enemies in them and the rooms are so close together it doesn't make sense that the king doesn't pool his resources a bit and just overwhelm the party.

Don't get me wrong, I enjoyed DMing the module and found it very easy to DM and loved the feel of it. The vermin and undead worked well together. I'm just going to have to spend a little time customizing the treasure a bit more sort of post fact.