A Puzzle and a Code

Last weekend the players found a dead messenger. On his body they found some mysterious symbols on a strange device: two wooden disks attached together so that the middle one turns...

I devised this as a simple puzzle for my youngest, but in practice the off-centre centre of rotation and the extra marks meant it took a few minutes to get it oriented correctly...

THE LETTER IS IN A BOX UNDERNEATH

The box took a bit of searching to find...

It's great sometimes when the players find something, to simply hand it to them and see what they do. One of them's bound to pick it up before they realise they should cast Detect Curse on it! Shaking the box revealed it contained something, but what?

A letter sealed (rather badly I'm afraid) with a Z (as per the Z in the middle of the puzzle wheel, which they had already noted). Quickly opening the letter they found...

Obviously mirrored writing, but my daughter impressed me by simply holding it up to the light to read. I don't think that trick is going to work for an LCD screen, so here it is again:

Evidently Zanquibar was the wizard they had located earlier, holding a pair of doors shut, both the doors and the wizard turned to iron. Below was the puzzle with the key to setting him free:

I promise you the solution is simple, though it kept the players happy for an hour. I gave them a hint at one point not because they needed it but as a little encouragement.

If you try and solve it you will see how it keeps your interest whilst you search in vain for the answer, it isn't a case of staring at it for an hour - you keep on finding things which might be the answer... but aren't... but which help you to the solution without you realising it.

(Note: it helps if you print this out to solve it)