Out of every 50 museums in the world, there will be one which has part of it closed off to the public. The security is unusually very strict near this area and it is very difficult to get past them. Should you manage to get past, you probably won't return. Although it is forbidden to enter this zone, it is possible to get a preview if you ask the curator before closing time, when nobody is around.
Once you have done this, dim lights will come on, forming a path and you will be asked to follow closely. As you travel through a myriad of ancient artifacts and incredible structures with mystical writings, you will find the exhibits getting wilder, crazier, too peculiar and profane for human viewing. Surprisingly, you will be quite sane when you are asked to swear an oath. Indeed, the curator will demand of you not to speak of what you have seen and heard. You will, whether by choice or compulsion, agree.
You will emerge into a room, mostly obscured by a ghastly mist. There will only be one noticeable attraction: a fireplace wall, with a clock above it. There will be a single wooden chair some distance from it; the curator will take his seat. He will direct you to that wall. You have no choice. He will instruct you to put your ear against the wall. Comply. Now you will hear the unmistakeable audible sensation of scratches and whispers and unholy fervent prayers among the crackling of the fires.
You will know with certainty that there is something grisly and morbid lying behind these walls yet strangely, you will feel a sense of pity and understand this is imprisonment. You will visualize a cell, green and sick, filled with the stench of death, decay, and wretched blood and dubious treachery but you will be unable to discern any physical presence in this room. This wickedness... how can you grasp it? It is exceedingly corrupt. The curator will confirm your suspicions but he will say no more, whispering, The Walls Speak Fears.
Sympathizing and yearning, driven by unfounded curiosity and having no feeling of dread, you will inexplicably request to remain at this wall. The clock ticks on loudly as the curator agrees. The curator will grant you your wish with one final exchange: Indeed, o foolish mortal, you have doomed yourself to a hellish twist. At the exact moment when he is about to leave for home, the distant lights will go out and the scratches will stir. The fires will stifle. Intrigued, arrogantly, you will speak. What you will hear in response will be deeply horrifying. Many go mad in anticipation of this reply. They are silenced when they hear it. If you are lucky, you will suffer neither of these fates. What is said is only known to you and is harmless but the mental image that is printed in your mind is what will scar you.
You must not show any sign of fear and sorrow when you are shown this image or you will be drowned in them, unable to leave for all eternity; all the dark and miserable memories you possess, repressed and suppressed, will be unlocked in that instance. You must then ask what the purpose of nightmares is. Immediately, you will hear words and curses in unknown language and you will find your answer lying before you. It is the cause of your despair. Destroy it and you will be able to live a life of happiness. But in doing so, you will have let loose this monstrosity into the world and you will be swallowed up living out your dreams with no realization of what happened to you.
Should you choose not to destroy it, be resolute in your choice for the creature's wrath is about to come upon you. It's shrieks, the clawing and savage growls and screaming and the absolute pressure of it's endless hatred will apprehend every part of your body. Your body will literally be begging you to submit as it feels being torn, flesh and veins, marrows and bones. Your eyes will shrivel and your mouth will be as fierce as the furnace that lies besides you... and beneath. Your lungs will gasp for air as the room is flooded with murky dark water, driven onward by a strong and evil wind that cannot be calmed.
Your feet will lose weight and hope and cementation in the wavering beliefs and morals you stand upon, as the voracious funnel of miserable fire and watery delight, the ultimate symbol of destructive doom and ethereal devastation, the one that devours everything in it's path and seeks out those which hide from it, that collects at the ceiling of this former sanctuary pulling you up, threatening to bring you up into a vortex of pure dereliction and mayhem.
Into the cacophony of every beast and every man crying out in agony, the crackling of burning flames and the shots of every gun shot heard throughout the world ringing in and piercing your exhausted ears until you can bear no more, the casualties and consequences of war and senseless killing seeping into your veins and bloodied eyes as you look down into the gun you wield; the tool you used to slaughter and put all your hate into. And you hear the maddened calls of the ravens in unison prying at your decaying flesh, serpents reaching out for you with lust, an invitation of disorderly death extend to you!
Your mangling will be one of billions that undergo this endeavor but should you... be resilient, you will find yourself unscathed and that foul wall will be burned and the room will be cleared of that mist as moonlight shines through on you. And written on that charred wall will be the answer you have been looking for, the answer to all nightmares, the life you should have lived, the life that you were expected of, the life that you abandoned. The life of simplicity. Sleep easy.