This is a very good monster manipulation and lynchpin hold with a consistent difficulty curve that starts around medium and gradually edges closer to upper medium by the end.
Level 1 starts out with puzzles centered around some of the most basic DROD elements, and each level after that adds a few more to the mix. In fact, I'd say that Levels 1 and 2 were probably my favorites; the elements used were limited and focused enough that it felt like a satisfyingly thorough exploration of their potential when used together. Level 4 adds a number of extra elements, and while none of the rooms with them are bad, none of them are given the level of attention that those introduced in the first two levels were which left me slightly disappointed. Level 5 had some nice slayer rooms, and though it too felt slightly underutilized, it was clearly meant to be a slightly harder conclusion to the hold, and I can't fault it for that.
Level 3, which is focused on tar and mud, was probably the weakest overall, with more rooms that test your ability to clear a lot of tarstuff and rooms that require you to guide a bit of mud or tar for hundreds of turns to a far off area of the room. Even if a few rooms here were a little tedious, it didn't bother me that much, it's just that many rooms on this level didn't feel like they fit with the types of monster manipulation rooms used elsewhere.
There were some rooms in the hold that had you complete part of a room in a different way before you could gain access to an entrance where you could clear the room, and I enjoyed these rooms a lot. On the other hand, there's a required room in level 3 that could very easily cause some backtracking issues, because you need to do a 'clear room, cut tar to unclear it, and leave' trick to reach it. There's a KDD Level 8 style warning about it, but even so it bothers me even if I figured it out puzzle quickly enough and enjoyed it. There's also points where better placed green doors would;ve allow you to avoid redoing dropping some trapdoors or orb puzzles should you need to backtrack, and checkpoints could've been a little less scarce, but I don't think any of these issues detract from the hold significantly enough.
Overall, I would definitely recommend this hold, and I think it might be a good choice for someone who finished JtRH and is looking for something slightly harder that builds on the skills they learned in there.
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aka VioletPumpkin