# The Thirteen Doors of Aj Noc'la

An entry in Fortnightly Topic Challenge #39: Deep Down in the Dungeon 1.

Having finally defeated the tyrannical wizard Aj Noc'la, your party makes its way through the door at the rear of the throne room. Presumably the dimly lit archway leads to the treasure vault...

"I wonder what he meant by 'exiting through the gift shop'...", the party's rogue muses aloud, recalling the wizard's hysterical, dying words. By way of answer, the air is split by a thunderous crack, as the door slams shut behind you. Spinning, you scramble to reopen it, but instead find only solid stone. Then, staring in disbelief, you watch as a gently glowing inscription etches itself across the wall:

Gaze upon this thing of wonder,
'Neath a sky where stars align.
Then with heavens torn asunder,
From the shadows comes a sign.

In the runes, the truth is dawning.
Can you hear which door will save?
Make your choice, but heed this warning:
Twelve doors hide an early grave!

Turning again, your eyes are immediately drawn to an enormous structure, floating weightless in the centre of the cavernous room. It is made up of nineteen identical cubes, suspended high above your heads by some unseen force. Affixed to the ceiling are a pair of glowing orbs, lighting the configuration from above.

Around the perimeter of the room are thirteen closed doors. They appear to be identical but for the fact that each is labelled with a different word, carved into a small panel above the frame. Your party quickly notes them down:

TOMB, EYES, DARK, FATE, ONCE, FORT, BONE, DICE, LIFE, FIRE, WAND, LOCK, GOLD

Knowing that the wrong choice leads to certain death, through which door should your party attempt to exit?

• Clearly the door marked LIFE is the one that doesn't lead to death. What's to solve? :-P – Rand al'Thor Oct 1 '18 at 12:00
• @Randal'Thor - I dunno... Doesn't life always lead to death? – Alconja Oct 1 '18 at 12:08
• Splendid drawing! – xhienne Oct 1 '18 at 13:44
• @xhienne - thankyou. :) Fun fact: it's 100% finger painted on my mobile. – Alconja Oct 1 '18 at 23:17
• @bornfromanegg - In total, I used 4 apps. First, I used a slightly buggy, but adequate 3d pixel art app called VoxelColor to get the initial block layout right. Then I traced a screen grab of that in Adobe Draw, aligning its perspective guides to help me sketch out the rest of the room. Next, I took that into Autodesk Sketchbook where I did all the actual painting (about 20 or so layers worth), before doing some final contrast tweaking in Snapseed. – Alconja Oct 3 '18 at 9:13

FATE

as pointed out,

Tearing the lights asunder causes them to swing to positions to the left and right upper sides. With light shining from those angles, the left light produces an image of F while the right light produces a boxy 8. Together, F + 8 = fate

Imagine the lights are against the upper edges (left and right). Now consider the light passing diagonally through the shape, at 45°. From the left light, the far right upper blocks cast a line of shadow. The blocks closest the light also cast a line of shadow, a bit 'lower' than the first line. The blocks closest to us, the viewer, line up in such a way the no other shadows are cast, while the blocks farthest away cast a line of shadow perpendicular to the other lines, forming an F. Drawing this out helps a lot.

OP edit: here's a gif that might help visualise the above explanation:

Also note that the clue poem states:

you will 'hear' the answer - cuing to the sound of 'fate' rather than an exact spelling. nice touch.

Brilliant puzzle - used to love these kinds of tricks in D+D.

• How can you tell from the image what the shapes would be? – Pureferret Oct 2 '18 at 13:29
• @Pureferret - I've also edited in a gif to help with the visualisation if you're interested (hope you don't mind, Stidgeon - nice work getting the solution, by the way). – Alconja Oct 3 '18 at 10:25

I think:

The correct door will be found by fitting the four letter words onto the cubes. There are 12 four-square-spaces visible in total - three on each of the three rods that extend towards you, two diagonals on the back wall facing away from you, and one diagonal facing you.

That will leave

one word that doesn't fit and that will be the exit door.

I haven't had time to work out

which words / letters would fit or how you would know which ones fit where but maybe someone else can improve this answer with that information.

If I take a stab at this...

Gaze upon this thing of wonder,

'Neath a sky where stars align.

This is talking about those two lights

Then with heavens torn asunder,

Maybe if you rip them off the ceiling

From the shadows comes a sign.

And shine them on the blocks at different angles, it’ll form letters.

We can see that

It already forms an O on the ground, but if you move the lights so that they’re in the top left corner of the diagram, I’m pretty sure the resultant shadow will be an F. If you remove the ring holding the lights together, one of the lights will shine the F in the top left corner. The other light might shine the RT...?

This means that

The door to go through may be FORT, since it’s the only door with an F and an O; but I can’t really see how to generate the R and the T as of yet.

• That's a wild guess for someone who's risking their life. – user7393973 Oct 1 '18 at 13:28
• I’ve already destroyed the wizard, martyrs make for better legends anyway – El-Guest Oct 1 '18 at 13:29
• If you look closely at the lights, there is a ring that holds them together. Would it be possible to remove the ring and... well you figure out the rest :) – Mixxiphoid Oct 1 '18 at 15:05
• @user7393973: If I've finished off the wizard the deathtrap is nothing to fear. – Joshua Oct 2 '18 at 17:38