I’m calling it here. My previous posts on Keys of the Wizard are needed for context.
The main issue I ran across: what probably are serious bugs. Why “probably”: the nature of this game makes it hard to tell what is a bug or not. Let me explain in context–

Via World of Dragon.
–so I booted up difficulty 3, saved my game, and started by systematically annotating my map with the locations of enemies and items. Both can move around (the Jester, for instance, moves items) but not significantly. This let me decide on an action plan.

I tried some “clever” methods but in the end the easiest thing to do was to scrawl upon my existing map with Microsoft Paint.
I noticed, while I was going through the process above, that difficulty 3 had more traps to deal with. One room starts shrinking, one has poison darts…

…and the room that had a statue I previously thought might have some sort of secret, turned out to also be a trap; if you enter the room from below it attacks you and takes out a chunk of damage.

This turns out to be much more worrisome at difficulty 3 than 1, as the monsters … well, they don’t hit for more per hit, but they last for longer, meaning they have more time to get hits in. The overall effect of combat really is like a typing game and since you can do more damage when healthy, if you can very quickly type in many hits at the start you’ll be at an advantage.

Notice how I was in the middle of typing “BASH ORC” but got interrupted at “BA”. No, you can’t keep going and type “SH ORC”, you have to start over from the beginning. I got good at typing CYCLOPS fast.
The game features a REST mechanic, with the catch that monsters will wander while you are resting and might whale upon you if they come across you. If you go to the Sanctuary at the start, this normally isn’t a problem, with one exception: the Wizard can teleport in.
This means, theoretically, if you could kill the Wizard, you’d be safe the rest of the game. You might think that means the game has locked the means of killing the wizard behind a whole sequence of events. Certainly the unicorn hints are more lengthy to deal with this time:
lantern + mask + feather -> deathring
dagger + feather + rope -> machete
plectrum + dagger + lantern -> manacle
spoon + plectrum + rope -> map
tome + rope + feather -> lance
tome + lantern + mask -> dragonsword
rope + lantern + feather -> jug
dagger + feather + rope -> machete
lantern + feather + rope -> scroll
(The same trick that works on Minotaur works here. When you find a unicorn, save, step east, go north X times, go west, and RUB HORN. You will get a hint. Repeat for X+1, you will get a different hint. Repeat for X+2 etc. until all hints are obtained.)
However, I realized the PISTOL and the BULLET that goes with it were pretty easy to get through the way my map was generated…

Bullet is the star on the left, pistol is the star on the right. This isn’t quite as straight a shot as it looks because the first one-way door requires having used the PLECTRUM on the ZITHER in order to open it, but it still isn’t hard to grab both items.
…so I decided to make a beeline for those items first, then try the pistol out on various enemies to see which ones I could insta-assassinate. The answer is none of them. I did between either 0 or 3 points of damage (out of 255).

The orc is the easiest enemy to fight in the game. Here I did 1 point of damage.
The fact that two items need to be united for all this to work makes the effect seem baffling and was one of the points that I suspect might be a bug. (Or maybe the pistol is only super-effective if you’re holding other item X at the same time?)
I decided to switch to the old reliable, the mace. That did work although it does somewhere 30 damage max (when you aren’t hurt) down to 10 (when you’re just a little hurt). So it requires chipping away at enemies, but all the enemies do roughly the same damage back no matter if they’re an orc or a dragon. Or a wizard.

With the wizard dead, things worked as I expected: going back to the Sanctuary and using REST let me wait out my health rising all the way back to 255 with no opposition. Based on the manual, there’s no particular limit to how often you can use REST (there’s items that protect you from enemy attack with a limit, but that’s not the same thing as just trying to use the action). The problem is, even though I could restore essentially an unlimited number of health points, I could only do it once; going back to the Sanctuary later and using REST again had my health go up 0. This feels more like a bug than intentional to me.
(Aside: going north from the Sanctuary on difficulty 3 works differently than on 1. On easy mode it teleports you back to the starting cabin; on difficulty 3 it teleports you to some random spot on the top floor. I found that the hedge maze area was not available in the route I had taken before, and the only way I could get in was via Sanctuary teleportation.)
I next tried making the JUG my initial priority. The JUG is on the list of items where you need other items first to do pickup (rope + lantern + feather); the items are in the open although it was a pain to wrangle all three and get to the right spot. Finally:

The jug has rum which heals you, but alas, it only works once; subsequent drinks are poison. Oh well.
Thinking some more, I decided to go for the DRAGONSWORD instead. Surely that’s a good weapon and will be more efficient than the mace?
tome + lantern + mask -> dragonsword
This is a more elaborate combination to get than the jug, because the mask is held by the cyclops. So I had to nab the mace, then club the cyclops, and then get the mask, tome and lantern together. Holding four inventory objects at the same time also requires some good health so I had to avail myself of the options I had (teleports still do healing, so I used one of those, plus I got zapped to the hedge maze once with a food ration and I used that). Finally:

I was excited to see at least the dragon fall before me in a flurry of blows, but no: the sword does zero damage, no matter what enemy I used it on or attack verb I tried.

Surely this is a bug?
Hence, that complicated sequence was for nothing: the best thing to do was to grab the mace which was already out in the open and use that for braining services instead. I suspect something went awry with the game’s tables.
I tried fiddling with the keys in lots of places, but never got them to do anything, sorry. I also found one of the unicorn’s hints told me objects I needed to pick up the Cyclops’s eye (which it drops upon dying) but I was able to pick it up just fine without any extra help.

I never even saw the dust.
If I had faith the game was behaving like it was supposed to I might try a little bit longer, but no, this is a good stopping point. I think I’ve extracted most of the “wisdom” anyway, so let me segue into a discussion of the adventure-roguelike.
It has been tried quite a few times now, and never with great success. In historical terms, I think the main issue was (unlike Adventure itself, or RPGs glomming onto Wizardry/Ultima) there wasn’t a good model to copy. I don’t think any of the authors even heard of each other, so they were all re-inventing their own personal wheels with their strengths and weaknesses. Mines to kick things off had very tight logic in terms of object and puzzle placement, but given that was the only real element to the game it became mechanical as a story. Lugi seemed promising, but puzzle solving was hard to do systematically. Minotaur did a good job making the map seem varied even when it was fixed but had to go a route frustrating design to even work (when Keys of the Wizard tried to tone down the frustrating design — most especially by ditching the magic system — it created a gaping hole where gameplay was supposed to go).
The Queen of Phobos got the closest I’ve seen to what might be the “ideal”, except it had too much fixed to really count as a full adventure-roguelike. Still:
a.) the game has four thieves you have to deal with
b.) each thief has a weakness that can be used to defeat it (like beer for one)
c.) alternately, there’s a grenade you can throw to take down any thief…
d.) …or even better, if two thieves are in the same room, you can take down two at the same time.
e.) If all else fails, you can cross your fingers and try your best to evade them.
I don’t think the key here is just multiple options, but multiple options which have different natures than just “solving the puzzle”. The beer option works well as long as you give it to the right enemy…
THE LOOTER IS HIGHLY INSULTED AND KILLS YOU. THEY MUST NOT DRINK BEER WHERE HE COMES FROM.
…but because the grenade can hit two enemies at once, it isn’t precisely symmetrical to using the beer (compare with solving a puzzle vs. using a wish in Wishbringer). Evading also results in a much different gameplay effect than either of the other two options.
So I’ll say a good adventure-roguelike will offer multiple solutions to puzzles but do it in such a way that the ramifications of how the solve is enacted results in different world-states. One solution to a problem might involve explosives but cause damage elsewhere (and a brand-new problem) while a subtler approach might avoid structural damage but corrupt the player’s mind with dark power which comes into play later. With enough “ramification effects” two playthroughs would end up being very different; the player themselves would be used as a source of chaos. While this isn’t the only thing needed to make such a game work, I’ve never seen it used systematically in combination with full randomization and I suspect it might make the genre a little more plausible.
Great work. The adventure+rogue like genre seems elusive, while your conclusions are instructive, though.