Lucid Nightmare Secret Mount – Guide
Lucid Nightmare is a Secret Mount obtained after decrypting a series of puzzles from the Mind-Seekers, Azeroth's enigmatic riddle-makers. Lucid Nightmare is one of the major secrets added in Legion, along with Kosumoth the Hungering, Riddler's Mind-Worm, Sun Darter Hatchling and Uuna.
Please note that this guide will be as concise as possible. If want to know more about each puzzle then click on the spoiler at the end of each section or check Blizzard's official post with insights and explanations.
Progress Macro
Important: Make sure to read the Inconspicuous Note after you solve each puzzle.
Use this script to track your progress:
/run local N,t,d={"DAL","ULD","AQ","DEEP","GNOMER","VAL","MAZE","MOUNT"},{47826,47837,47841,47850,47852,47863,47881,47885} for s,k in pairs(N)do d=C_QuestLog.IsQuestFlaggedCompleted(t[s]) print(k,"=",d and "\124cFF00FF00" or "\124cFFFF0000NOT","DONE")end
Note #1: Secrets of Ulduar
It begins in the 2104059.
With a most pleasing sign.
(These letters will not always rhyme.)
The first note is found on a table at the top level of Curiosities & Moore in Dalaran.
Solution: Go to Ulduar and find the Rusty Lever and in the North-West corner of the Scrapyard. Click the lever, and a 20 by 20 grid of Scrapyard Lights will appear on the floor of the room. Click the lights to form the pattern below and then the Inconspicuous Note will appear.
Note #2: Mindcraft
1000 years imprisoned.
Surely it wears on the mind.
Head to AQ40 and make your way to the end of the raid. Go past C'thun, past the 3 NPCs, and at the top of the stairway there will be an altar with a Mind Larva on it. Click it to start Mindcraft, a minigame similar to JewelCraft.
Solution: Match five brains in a row to win. Note that even though Blizzard's article suggests that matching five brains is the only way to win the game, multiple people have confirmed winning the game after playing for a while (anywhere from 10 to 30 minutes), possibly by reaching a certain number of hidden points.
Note #3: The Chair
Deeper than deep.
Awaits your seat.
Before going further, you'll need to get a Shadoweave Mask. You can buy it from the Auction House or craft it yourself if you have Tailoring and the Pattern: Shadoweave Mask. If you don't have the pattern, you can get it from Dark Iron Steamsmith in Searing Gorge.
Solution: Go to Deepholm, enter the Crumbling Depths and interact with the Dark Fissure.
/way Deepholm 58.3 25.5 Crumbling Depths entrance
/way Deepholm 63.8 22.5 Dark Fissure
A fissure in the ground, barely wide enough to squeeze through. It's too dark to see anything, but you can tell that it is very deep.
> Drop into the fissure.
WARNING: You are about to fall into a dark fissure. You may not be able to climb back out again. Are you very sure you want to do this?
Accept the warning! You have now fallen into a Deep Cavern. Find the chair with the Dingy Plaque behind it.
The plaque is old and barely legible. You can only make out fragments of each line of text.
Supremacy?
Get...
Shirk...
...eke...
Solution: Equip the Shadoweave Mask, interact with the Strange Skull on the chair and a new note will appear.
Note #4: It's Binary?
Where the shaded delegate may appear.
Enter Gnomeregan and go to the Engineering Labs where you'll find a wall with 10 Numeric Consoles and a plaque with instructions.
01110111 00100 10010110 10101
11110111 01100 01111111 01000
011010111001011010010110 10111101
11001 00111111 10010 01001001
10000 011010010110100111010110
01011011 11110 11110001 11111
11100000 00010 11111111 01000
10110111 10101 01111111 00001
10101110 11111 00110000 01000
101101010010101110010110
180
+1111111111
Solution: Set the consoles to 1222176597
You can use the following scripts as macros:
Up: /script SelectGossipOption(1)
Down: /script SelectGossipOption(2)
Solution: Set the consoles to 1222176597
You can use the following scripts as macros:
Up: /script SelectGossipOption(1)
Down: /script SelectGossipOption(2)
Note #5: Nightmare Tumor
Games and toys are left behind.
When you awaken screaming.
Solution: Go to Val'sharah, find the Nightmare Tumor and play the Eyecraft minigame where you'll have to uncross the optic nerves of Il'gynoth's many eyeballs. This minigame is similar to Blingtron's Circuit Design Tutorial.
Il'gynoth will whisper to you "AL'KSH SYQ IIR AWAN? IILTH SYTHN AQEV." which translates to "Is this real or an illusion? You are going mad."
/way Val'sharah 66.4 36.5
Note #6: The Endless Halls
What you seek is buried within.

Secret-seekers, naturally, would seek the Tomb of Secrets (within the Valley of Emperors) in Kun-Lai Summit, wherein secrets are buried. There, you’ll find an urn you can interact with to consume the ashes of an evil sorcerer (seems like a good idea). When you wake up, you will find yourself in an endless maze.
We sought to create a puzzle that couldn’t be completed by just following a guide. Thus, the Endless Halls is randomized based on your player ID, as well as the day of the week. Very few players will ever see the same layout, and coming back the next day will present you with an entirely new challenge. - Developer note
/way Kun-Lai Summit 53.3 49.3 Tomb of Secrets entrance
/way Kun-Lai Summit 52.8 52.1 Urn
Runes on this urn indicate that it contains some of the remains of a powerful mogu spirit-binder. Many of the markings appear to be warnings.
> Consume the ashes.
WARNING: You are about to consume the ashes of an evil sorcerer. There is no way to tell what will happen. Are you VERY sure you want to do this?

The Endless Halls is a cruel, uncompromising maze, designed to confuse and disorient at every turn. You start in a nondescript room with foggy exits in the four cardinal directions (N/E/S/W), though some are blocked by rubble. Going in one of these exits will fade the screen to black, then fade back in with you in the connected room.
The goal of the maze is to find 5 colors of orbs (red/blue/green/yellow/purple), and deliver them (carried one at a time) to the 5 matching colors of runes. However, several mechanics make this much more difficult than it may sound.

The maze is arranged on an 8x8 grid of rooms. Each cell has between one and four exits. However, if it would have 4 exits, it’s actually not a single room, but two two-way rooms that occupy the same space, but don’t intersect. These Non-Intersecting Cross rooms are the first major source of confusing discontinuity, and also cannot contain any Orbs or Runes.
The second main source of disorientation is the edges. They loop around, but not directly. Instead, exiting one end of the maze will send you to the other side of the maze, with an additional offset. This makes it very difficult to tell what room you will end up in if you cross the edge of the map. You can, however, reliably backtrack from your new position to your previous position. Many players made frequent use of this backtracking to reliably navigate the maze without getting lost.
In addition, there is one final wrench thrown into the gears: the Teleportation Trap. Within the maze, a single room is the Teleportation Trap. When you enter this room, you are instead secretly teleported to a random room in the maze. Once you’ve identified the Teleportation Trap room, avoid it at all costs!
Once you’ve dropped the fifth orb off at its matching rune, the next exit you travel through will takes you to a golden room with the next Inconspicuous Note.
Anatomy of an Endless Halls Maze

We learned a ton from how the Endless Halls were experienced by players. Overall, it was an exciting and unexpected part of the series, but a few things could have gone better. By putting the hardest and most involved puzzle at the very end made players trickle through the finish line, depriving the community of the mass celebration moment as everyone who had been working hard on it together completed it at the same time.
Most importantly, the variance in difficulty of different mazes led to some being easily solved by wandering randomly, and some requiring careful mapping to finally solve, leading to frustration for the few with especially challenging mazes. While having individual mazes turned out great, the difficulty variance was just too high. We’ll keep all of this in mind for next round, and thanks for the community suggestions that we add jump scares. Good call! - Developer note
Resources
If you need help with the Endless Halls, we recommend you get the Lucid Nightmare Helper addon. The frame generates "rooms" as you move through the halls, which you can use to retrace your steps to the rooms you'd previously marked that contain an object of interest.
After you have found a special room, start mapping until you find another one. Then go back to the previous room to make sure that you haven't triggered the Teleportation Trap. Repeat this process until you have found all of the rooms.
Once you've dropped the fifth orb off at its matching rune, the next exit you travel through will takes you to a golden room with the next Inconspicuous Note.
Note #7: The Forgotten Crypt
The way is now open.
To the greatest secret never told.
A fitting end to your journey.

The clue here is a reference to a place in the world that has long been a secret to those in the know, but has never been used—the horrendously creepy Forgotten Crypts in Karazhan. In the game since the WoW’s initial launch, exploration-focused players ventured into these crypts for years after each patch, in the hopes of finding some newly-added secret. They were perpetually disappointed—until now.
This time, sitting on top of a pile of bones near the bottom of this huge-but-empty crypt (within The Pit of Criminals) is a chest containing the Lucid Nightmare.