Though many who worked with Iris may have assumed she'd have an ‘I'll sleep when I'm dead' mentality, she actually had fairly decent sleep hygiene, much preferring the productivity of restfulness to wasteful hours of weariness.
Her bedroom had acoustic panelling with thick curtains, and she slept upon one of the most advanced smart beds available. It continuously adjusted its firmness, position and temperature to maximize her time in deep sleep, and would only wake her in the morning during a light sleep cycle. Her purple sheets were spun from bamboo with anti-microbial silver threads, as were her MC&D branded nightshirt and socks, which made her look more adorkable than she would care to be seen as in public.
After a routine of reading and cocoa, she turned on her ambient music and crawled into bed. The only thing that made tonight different from any other night was the incantation she recited in her mind, over and over again, until she fell asleep.

The next thing Iris knew, she was in a long stone hallway. A hellish orange light poured in from a row of windows on the left-hand side, illuminating a collection of portraits, statues and furniture on the right. The windows were stained glass, and she couldn't see what was on the other side. She could, however, hear a distant clamour, along with a rumbling like thunder.
She reached out to touch the window, only for her hand to phase through it, like a glitchy video game. This startled her for just a moment, but it reminded her of what she had been doing before she fell asleep. She looked at her outstretched hands and saw that they were distorted, and when she tried to poke her left palm with her right index finger, it passed through without sensation.
These simple reality checks were enough to confirm that she was dreaming. She looked down to see that her dream form wasn't in her sleepwear, but her preferred outfit of a turtleneck and dress slacks. This was fortunate, since if she ever went on a business call without pants, even an imaginary one, she never would have heard the end of it from Ruprecht.
She set off down the corridor, the sound of her footsteps absorbed by the crimson carpet beneath her feet. She resisted the urge to inspect the castle's décor, but she nonetheless took note of it as she passed. The pillars were richly carved with frail, naked human bodies contorting and screaming in agony. The golden runes embroidered upon the (now scarlet) carpet were of the Chaos Tongue, the mosaics of the stained glass windows broke into incomprehensible fractals, and the statues were of impossibly nightmarish creatures that could only exist in the darkest dreams.
The portraits mainly depicted the individual she was here to see, almost invariably in scenarios that demonstrated the brilliance and terror of his reign and the futility of opposing it. There was a portrait though that gave her the slightest of pauses: a younger, more vibrant version of the Dream Tyrant along with four other men, seemingly at ease with each other and discussing business. The men looked so much alike they could have been brothers, and one of them was especially familiar to Iris.
She walked past door after door, not bothering to check any of them. She knew they were all inaccessible, and none held what she was after anyway. After what felt like a long walk along a route she could not precisely recall, she finally reached a pair of slightly ajar doors at the end of the corridor. The right-hand door creaked ominously as she pushed it open, illuminating an opulent but unkempt throne room. Upon the throne sat The Nightmare King of the Dream Palace; an aged, skeletal man dressed in scarlet robes with a golden crown nailed upon his head, his white hair and beard growing to the floor after ages of neglect. He was covered in dust and cobwebs, and if Iris didn't know better she would have thought he was a corpse.
The King gave no sign he noticed her, or was even alive at all for that matter.
And Iris certainly hadn't walked all this way just to be ignored.
“Your Majesty,” she said loudly, her voice echoing throughout the chamber, vibrating the walls and shaking loose dust and debris.
The King was finally roused, slowly lifting his head to look at the intruder with his unnaturally deep-set eyes.
“Who dares. Who dares. Who dares,” he repeated in his raspy voice, each iteration growing softer until he fell silent once more.
Iris gave him a moment to finish his sentence, but became worried he had fallen asleep again.
“Ah, I dare?” she replied at last. The King shook his head, resenting his own apathy to deal with this insolent interloper.
“Name yourself, dream walker,” he said, still unable to raise his voice to anything louder than a mumble.
“Dark,” she said proudly. This got the King's attention. He rose from his chair, squinting at her, trying to divine whatever other information he could.
“Brother?” he asked uncertainly. “No. Not entirely, anyway. He'd be less human now, not more. You share his Name though. His latest proxy then? What happened to Benjamin?”
“World War II, I think. Don't quote me on that though,” she replied. “My given name is Iris, by the way. A pleasure to meet a being of your standing.”
“Former standing,” he said bitterly, reclining back in his throne. “Leave me to rot, woman.”
“I gave you my name, please use it, and I was actually sent here to see how you're doing. You've not taken any fresh victims for almost a decade now. My Grandsire, your brother, is concerned about you.”
The Nightmare King coughed out a horse laugh.
“Is he now? That's the only reason he sent you? Brotherly concern? There's nothing he wants of me?”
Iris paused for a moment, considering her response.
“We did have a recent incident with the Oneiroi,” she admitted. “We were able to resolve it diplomatically, but it would be preferable if we had a contingency in case there's another incident.”
The King just chuckled at the blatant agenda.
“And Darke – or Percy, is what he's been calling himself? He wants to make a deal with me?”
“We have the largest store of anomalous objects and services in the world. Surely there's something we can offer you.”
“I don't doubt it, and yet I have nothing to offer in exchange,” the King shook his head. “Look at my Palace. It's falling to ruin! My fields all lie fallow, my serfs idle in starvation, my Knights have long since abandoned me! My Kingdom is but a shadow of its former grandeur, and I am a mockery of my prior majesty. After all these long centuries, I have been rendered impotent, neutered, declawed! I can not muster an army to fight the Oneiroi. Darke had best to look elsewhere. There's nothing left here but bones and mildew.”
Iris stepped right up to the Nightmare King, taking his pulse on his wrist. He made no effort to resist her.
“You're weak, starving, but you still have your craft, do you not?” she asked. “You can make and sustain oneiroid thoughtforms with fear harvested from human minds. Why did you go so long without feeding? Why did you let yourself become too weak to work?”
The Nightmare King looked up at her, his eyes wet and wide like a frightened child's.
“I was scared,” he said softly, hanging his head in shame.
“Of what?”
“I, I crossed borders, from here to the waking world, for the first time in far too long. I was seeking Knights, living creatures who could inspire unparalleled terror in the minds of men for me to harvest. But I was arrogant. I thought that because I could terrify lone mortals whilst they slept helplessly, I was a great, grievous ghoul whom none could defy. But as I walked the waking world, I found my corporeal form dishearteningly frail, and that my powers over the minds of others did not stretch as far as I had thought. I attacked a village, slaughtered over a dozen hapless idiots, but was slain by a common hunter with a rifle, like a glass-eyed doe in the woods."
The King covered his face shamefully, shuddering at the memory.
“When last I walked the Earth, firearms were weak, inaccurate, and could only fire a single round at a time. They troubled me not. But the weapons of this era are ungodly things, equal parts terrifying and empowering depending which end of the barrel you're on. When the hunter came, I tried to make him flee, but his faith in his weapon was enough to overcome any fear I was able to instil in him. I was beaten by a gun; physically and, more importantly, emotionally. The King of Nightmares was defeated with an off-the-shelf hunting rifle."
"I understand that your powers are limited in the real world, but why would a single bad excursion stop you from harvesting people's fear?" Iris asked.
“Because after that single excursion, my Knights left me," the King replied. "They saw me for the fragile old fool I was, realized I was of no real use to them. I was shaken myself, so shaken I couldn't even make Night Terrors anymore, even in my own Kingdom. So instead I secluded myself here, let myself and my kin starve, and now I couldn't feed even if I wanted too. I'll never die, not really, but eventually I'll fade enough that I'll be practically nothing. Please, my niece, just leave me here to rot.”
Iris did not heed the old man's request. Instead, she picked up his sceptre that lay askew by his throne. After wiping the dust and blowing off the cobwebs, she handed it to him.
“Show me your Kingdom, uncle,” she commanded. The King's lip snarled at her insolence, and yet there was too much of his elder brother in her tone for him to dare refuse. Using the sceptre as a staff to support his decrepit body, he rose from his throne and hobbled into the hall, dragging the spider webs behind him like a gothic wedding train.
When they came to a heavy set of doors, the King gestured for Iris to open them. She complied, revealing a balcony overlooking The Nightmare Kingdom. It retained remnants of horror; a rusty orange sky with a black sun and blood red clouds. The ponds and streams and river all flowed with blood as well, and the land surrounding them was blackened muck. The was a forest of dead black trees, a village of crumbling stone buildings, and a range of dark jagged mountains in the distance. But in every location - blood or land, forest or field, village or mountain - there were the decaying skeletons of all sorts of unnatural creatures. A few lethargic monsters still lumbered about, their nightmare forms no doubt greatly diminished from what they had been a mere decade earlier.
“What a sorry sight,” Iris muttered.
“I hope that means you've seen enough. Leave, return from whence you came and tell my brother I no longer have an army.”
“You still have some subjects left. With enough fear, they could be made strong again, made legion again. There's nothing wrong here that can't be fixed.”
“Have you not been listening? I have no Knights to spread fear for me anymore, to cultivate terror in the waking world for me to harvest. I do not have the strength anymore to invade dreams of random mortals in hopes of stumbling upon unconscious horrors.”
“I'm not suggesting that you do. I have something better than Knights for providing you with workable victims; I have data. Every day, in the modern waking world, billions of people divulge innumerable volumes of personal information on social media, free for anyone to find. I'm already set up for data mining. There are millions upon millions of people suffering from post-traumatic stress, crippling anxiety, sleep paralysis and any number of other horror-inducing conditions discussing their maladies online right now. All I have to do is punch in a few parameters, and in a fraction of a second, I will have uncovered more perfect potential victims for you than every single one of your Knights ever brought you in a thousand years.
“I can provide you with the names and location of victims. I'll start you off easy, give you time to build up your strength and, more importantly, your confidence. Think of what you could do with an inexhaustible supply of ideal victims, without wasting time hunting or working on duds. You and your Kingdom could grow even greater than you were in your hay-day, perhaps even so powerful that one day you could walk the waking world again without fear that any gun could put you down. Doesn't that sound better than cowering in your throne room for the rest of time?”
The King walked to the edge of the balcony, gazing out mournfully upon his ruined kingdom, dreaming of everything it once was and could be again, if only he could find a bit of his old courage.
“I'm not sure I believe you. It sounds too good to be true. But if you were to provide me with suitable victims, I suppose I have nothing to lose.”
Iris reached into her ear and pulled out a neatly folded piece of paper from her memory.
“I had a feeling you'd say yes. I've got thirteen people already to go, listed in order from weakest to strongest. Just send a ravenwave to your brother when you're ready for more, and he'll let me know. Do not come into my dreams uninvited.”
The King took the list cautiously, as though he feared it was booby-trapped in some way.
“And in return?”
“Your newly invigorated army of Nightmares will be at the service of Marshall, Carter & Dark Limited,” Iris replied. “Within reason, of course.”
“Of course,” The King nodded sceptically. He unfolded the list and began looking over the names she had brought him. “If these mortals prove as promising as you say they are, I'll have to Knight you.”
She mulled this over for a moment.
“Does that mean I'd have to swear fealty to you?” she asked.
“It would indeed.”
“I'll pass then. My loyalty is to myself first, those who are of use to me second.”
The King laughed dryly at her open self-interest.
“Worthy of my brother's Name then. He chose you well. Regardless of the honorific we settle on, you'll be a valued ally of my Kingdom, as will my Kingdom be a valuable ally of yours.”
Iris looked out upon the desolate landscape, taking in the latent potential of those fallow fields, festering forests and forsaken fiends. Even the mere threat of such an army would negate the need for them to ever placate the Oneiroi again, and the power of Marshall, Carter & Dark, her power, would extend to both the material and immaterial planes.
And she would be able to sleep even easier, knowing that the King of Nightmares worked for her.