Well, I've reached the final (I think?) area, though there are still things along the way I haven't solved - I have no clue how to obtain the golden wand, and while I unlocked the Moon Pool, I have no idea how I've done it. Any hints?
Well, the Moon Pool unlocks once you complete the Bestiary (I think) though it's honestly just a dev room. As for the golden wand, that's a big ol' secret, so I don't know how much I want to share. I will say, though, that the clues to start you on your way are in places you've presumably already been, and you'll have to think outside the box (or be lucky) to reach your end goal.
I think I have an idea, but I've managed to get myself stuck inside the Mouse King and unable to transform into a snake to scare him off again. And then I misclicked on New Game. I'm not sure if I have it in me to replay everything from the start, sadly. (Maybe some sort of confirmation would be good there?)
Anyway, I've come to the conclusion that the wand the Mouse King has is nothing but a red herring and I think I know what the big ol' secret is, thanks!
Update: Replaying turned out to not be that much of a hassle, knowing what to do and in what order makes a huge difference.
Still not sure how to get the Golden Wand - I've been attempting the path of snakes and shields, but I can't get it to work. Adjusting for the difference in how the maze works doesn't seem to do anything, and neither does mirroring the directions, so I'm completely stumped.
Again, you're on the right track, but you may be relying on the wrong hints. Try looking around in Monster Town and the Dragon's Lair. There may be something helpful there if you can find it. Also, sorry about the bug and then restarting! I think I have an idea what might have caused you to get stuck, but I'm not 100% sure. Guess I'll have to look around!