They had been galloping for several hours. The road, initially marshy in the area near Red Bridge, had given way to countryside, and even the rain that had drenched them for a long stretch had abandoned them, leaving them with wet clothes and bodies numb from the wind as they galloped through the night.

  The barking of dogs near the farms that dotted the landscape was the only sound besides the incessant clatter of hooves on the dirt road. Nico, the last in the cordon led by Gareth, as always at the head of the expedition, felt his hands aching from gripping the reins too tightly for too long. His back and legs were no better. From time to time, Nico turned around, trying to see if there were any pursuers in the darkness.

  Then the terrain became more rounded, replacing the countryside with low hills and gentle grassy slopes. Gareth led the group to a hilltop and stopped. Nico pulled on the reins too sharply and almost fell off his horse, driven by his gratitude at finally touching the ground and his growing inability to remain in the saddle. However, he knew that they would have to continue their journey on those animals.

  After tying his horse to a low branch to rest and stretch his legs, he sat silently next to Leo, no one daring to speak. From there, they could see the road they had traveled and the road ahead.

  Nico watched a thick column of black smoke covering the starry sky, finally clear after the rain. The small town of Red Bridge had been hit hard that night, and it was because of them.

  A faint howl broke the silence; Nico felt a pinch on his side. The sound was hoarse and broken, as if the throat that emitted it were torn. The echo conveyed hunger, not for food, but for living flesh. Everyone turned to look in the direction of the road they had just traveled. Other howls from different directions answered the call.

  “Wolves?!” Leo muttered, “In this damn game, you can't even rest for five minutes in peace.”

  Nadia shook her head. Her neck was tense, her eyes lit by the moon, fixed on the distant howls. “No. This is the song of the furious hunt.”

  Kiah turned, her eyes wide, staring at the Princess.

  “Don't tell me you've read about this too,” Leo muttered to his friend.

  Kiah didn't answer.

  The Princess continued: “The Black Hounds have been set free. Flee their song, which drips with blood and reeks of death.”

  “I thought they were legends,” Kiah whispered.

  The Princess shook her head: “Ever since the Nothing began attacking us, legends have become reality and reality has begun to crumble.”

  New howls were heard, closer than the previous ones.

  “Um, so are we going to do something?” said Leo with an irony that betrayed his anxiety. He jumped to his feet: “Maybe we should get on our horses and flee at full speed, what do you think?”

  “They're close,” said Gareth, ignoring Leo. “Twelve, maybe fifteen miles at most,” he added, his hand on the hilt of his sword, ready to draw it as he surveyed the black landscape.

  “Do you think you can do it?” said Gareth, looking intently at the princess.

  Nadia nodded and stood up, slowly and regally, her blonde hair slipping softly out of the hood of her cloak, which fell behind her shoulders.

  Nadia moved to the edge of the hill as the howls grew closer and the itching in her side became almost unbearable. Kiah glanced at him sideways, but Nico shook his head as if to dispel a thought.

  Nico saw Nadia, illuminated by the blue moonlight, inhaling air with her eyes closed, probably in an attempt to calm herself. Beyond the girl, a barren landscape stretched out below, the farms and small clusters of houses far away from that area.

  Suddenly, the thick, fragrant air, with that damp smell of earth and leaves that the night has, changed, making him wrinkle his nose. Next to him, Leo retched, and Nico put a hand to his mouth to stop himself from following suit. The air was foul, as if a rotting carcass were decaying at his feet.

  “There they are,” said someone next to him.

  In the darkness, seven large shapes were coming from different directions, converging on them. He could see their eyes glowing red in the night, like flames of a devouring fire.

  The howling had ceased, and Nico couldn't tell if it was because they had been spotted or because of what they were: shadow beings like the Nerakth, who caused light and sound to wither away in their wake.

  Nico saw Nadia open her hands, palms facing the sky, as if in prayer. A thin silver chain slipped out of Nadia's sleeve, as if it had been waiting for this very moment. The white crystal tied to her wrist swayed in the air, capturing the moonlight and amplifying it into an almost blinding glow.

  Nadia's hands caught fire, not just any flame, but a living wave of red and orange that enveloped her fingers. The air trembled, grew warmer, almost vibrant, and in a single gesture, the incandescent spheres shot off, cutting through the night like meteors.

  Instinctively, Nico stepped back, shielding his eyes.

  For a moment, the darkness was swept away, revealing everything in a tremendous flash: the hills, the faces of his companions, the black, rotten bodies of the hounds, enormous creatures as big as ponies, running towards them with fangs dripping with saliva and blood.

  When the fireballs exploded against the creatures, the roar echoed across the hilltop and Nico felt the ground vibrate beneath his feet.

  Nico prepared to cheer, but the tension around him was still high. He shifted his gaze from the burning land to Nadia. The princess did not wait for the outcome of that first strike but continued. Nico saw only her shoulders stiffen, her arms rise again, the light of the crystal pulsing ever stronger. Something in the air changed, a buzzing sound.

  A huge mass of black clouds gathered above the heads of those offspring of Nothingness, hurling silver lightning bolts that branched out to strike different targets.

  A small hill collapsed, crushing bones as the earth swallowed them voraciously.

  “Holy salami!” exclaimed Leo, giving voice to everyone's amazement.

  Nadia staggered, clearly shaken, and Gareth behind her was ready to support her.

  “We have to go,” she murmured in a faint whisper, “there may be others on our trail.”

  Gareth nodded, helping her onto her horse.

  They had been riding for half an hour. Dawn was breaking behind the mountains, painting the clouds pink, when Nadia slumped and fell from her horse. Gareth was immediately by her side, and Kiah clumsily dismounted and rushed over to them.

  “She needs to rest,” Kiah murmured, resting the princess's head on her legs.

  Gareth nodded.

  Not too far from them was a small beech grove. They struggled through the branches, Nico pushing aside the damp foliage to allow Gareth, who was carrying the princess in his arms, to pass. Leo and Kiah were just behind, holding the horses by the reins. The trees suddenly thinned out: a small clearing opened up in front of them, a clear pool of water glistening in the light filtering through the canopy of leaves above. It looked like a place that didn't want to be found.

  “Holy salami! We're sure to find treasure here.”

  Nico laughed. His friend was obsessed with that kind of thing. He remembered him saying something like that before, but he couldn't quite remember when.

  “He has a high fever,” said Kiah. “We need to light a fire.”

  “No way, we could be spotted,” said Gareth curtly.

  “I don't know about here, but where I come from, you have to rest and stay warm when you're not feeling well,” replied Kiah, pointing an admonishing finger at Gerath, “and drink lots of fluids,” he concluded, almost to himself, then shook his head, “but that's out of the question if he doesn't wake up... Right!” he said, clapping his hands. "Grampasso. Silver. You go and look for some wood. Gerath, see if you can catch some fish so we can eat something decent. Let's try to avoid dipping into the food supplies the innkeeper gave us unless we have to."

  “What about you?” asked Leo, crossing his arms over his chest.

  “I'll look after the horses and the princess, but if you have any problems, we can swap,” said Kiah dryly.

  Leo shook his head indignantly. “Let's go,” he said to Nico, staring at Kiah over his shoulder. “Who made her the leader of the group?” he added with a slight snort.

  Nico and Leo ventured into the trees, which were still dripping from the night's rain. It would be difficult to find dry wood for a fire, he thought.

  After a while, however, Nico saw an old fallen tree, half lifted by another plant. He knelt down, slipped his arm into the dark space, felt a disgusting scurrying on his hand, and instinctively pulled his arm out.

  “What's going on?” Leo asked, clutching a soggy branch in one hand.

  Nico shook his head amused: “A few spiders. Come on, I think there's something here, give me a hand.”

  Satisfied, they returned to camp carrying a bundle of cracked but dry wood each.

  When they returned, they saw three large fish, still glistening with water, lying on the ground. Kiah was sitting nearby, an open book on her lap, and from time to time she looked up to check on Nadia, who was lying down with a cloak as a blanket and another as a pillow. The princess was pale, beaded with sweat, and muttering incoherent words in a feverish whisper.

  Kiah touched Nadia's forehead with the back of his hand, then went back to his book. A little further away, the horses, freed from their saddles, were grazing on the grass.

  Leo put the wood down on the ground, snorting, “I hate fish...”

  Kiah raised an eyebrow, then laughed as Gareth approached the wood and struck a spark with a stone, which immediately set the entire pile on fire.

  They ate the three large grilled fish, sitting in a circle around the fire. Nico still had the taste of smoke in his mouth when Gareth got up, dusting his hands on his pants and announcing that he was going to scout around and look for more wood.

  Nico watched him as the sword master walked away into the trees. Kiah got up and went to the spring, a white cloth in her hands. She returned with the damp cloth and placed it on the princess's forehead. Leo, lying on the ground with his hands behind his head, jumped to his feet as if he had forgotten something important.

  Nico followed his friend's movements as he rummaged through leaves, stones, and bushes, looking for who knows what. Nico was also looking for something, but in his mind. He had to say something to Leo and Kiah, even though he couldn't remember what.

  “I've searched every nook and cranny,” said Leo, returning from his patrol, this time from behind a pile of rocks. “Nothing. I would have expected at least one artifact... I don't know, a sword or a helmet... what a disappointment,” he said, throwing himself down next to the fire.

  “Wow! What an intense few days,” sighed Kiah, smiling condescendingly at Leo.

  “First the attack on the palace, then Red Bridge and the Hounds... and we still don't even know where we're supposed to go. This game is pure realism.”

  “Well, if you like that kind of thing,” muttered Leo.

  “What kind of thing?” asked Nico.

  “The kind of game that keeps you stuck for a whole day doing nothing because you have to look after the NPC on duty who got a fever from casting too powerful a spell,” said Leo, gesturing towards the princess.

  “This is pure immersion,” replied Kiah, then shook her head. “You don't understand anything.”

  Nico had a flash of memory, something about an article, but a kind of fog clouded his thoughts. He shook his head: maybe it was just fatigue. He decided to speak anyway; he didn't want to let that fragment slip away. Perhaps, once the conversation started, his mind would do the rest.

  “Listen,” he said, cutting off that inconclusive conversation, “I was waiting for the three of us to be alone.”

  He frowned, trying to remember what he was supposed to say.

  “What's up? Are you bored and decided not to log in anymore?” Leo said dryly.

  Nico looked at Leo, frowning. “No!” he exclaimed. “It's just that I read an article.”

  “Science? Culture? Technology?” Kiah asked excitedly, suddenly in her element.

  “Neuroscience... I think,” Nico replied hesitantly.

  “Cool,” said Kiah with a smile, “go on.”

  “Um, something about...” Nico shook his head. That gray fog in his mind had turned into a black abyss. “I can't remember anymore.”

  Kiah frowned. “Strange. You sleep badly, you remember badly... maybe you should see a doctor.”

  Leo snapped ironically, “Mom, what a drama queen. You're really exaggerating, Kiah. If you sleep badly or can't remember something, you have to see a doctor? Really? Come on, if that were true, half my family, including me, would have to be hospitalized.” Leo laughed again.

  Kiah crossed her arms over her chest and lifted her chin, assuming her usual know-it-all air: “As I said, sleeping badly with the visor...”

  “Nico, forget it,” Leo interrupted her. “This one reads too much for my taste.”

  Kiah got annoyed: she grabbed her bag with a sharp movement, muttered something incomprehensible as she rummaged through it, then pulled out one of her books. She opened it on her lap with a thud and took refuge in reading.

  Nico was dozing, his back leaning against a branch, enjoying the breeze in his hair and the smell of damp earth, while Leo, not far from him, was snoring loudly.

  Hearing Gareth returning from his patrol, Nico jumped to his feet, feeling guilty, caught in the act.

  Gareth was carrying a pile of wood so dry and perfect that it looked like it had come from a warehouse. When he put it down, he said, “We'll take turns resting. There will always be one person awake,” he said in a tone that brooked no argument.

  Stolen from Royal Road, this story should be reported if encountered on Amazon.

  Leo sat up, awakened by the sword master thundering his rules, and Nico refrained from laughing.

  “I'll take the first shift,” Gareth concluded curtly, glancing grimly at Leo, who snorted irritably. His friend muttered something that Nico couldn't hear as he turned away and curled up in his cloak.

  Nico, imitating Leo, wrapped himself in his rain-drenched cloak, listening to the rustling of the horses grazing on the grass and the measured footsteps of Gareth beginning his rounds. He was tired and soon fell asleep, but not for long.

  He could hear the horses not far away, the breeze rustling through the trees, and then a gaze, always the same, cold and fixed on him, but there was something else, not outside, it seemed to be inside, a disgusting feeling, something slithering like a disturbed snake digging for a way out.

  Gareth pulled him up to a sitting position with a small kick of his boot in his side. Nico jumped.

  “Ah, were you sleeping?”

  Nico nodded irritably, struggling to his feet, his eyes heavy with sleep. “Well, of course,” he said reproachfully, “what did you think I was doing? Watching the air while lying down?”

  Gareth grunted. “You haven't been still for a second. You've been scratching your side the whole time.” Then he moved closer: “Let me take a look. Do you have a wound? If it's infected, we need to...”

  “I'm fine,” Nico said curtly, pushing Gareth's hand away.

  The guard grunted. “Do as you please. I'm going to get some rest. Keep your patrols short and close by, and keep your sword handy.” He added a piece of wood to the fire and, after glancing at the princess still lying near the fire, he leaned close to the flames without his cloak, curled up on himself.

  The cloak covering the princess was probably his, Nico thought.

  He made a brief patrol, his side bothering him with its itchiness. He sat down next to the small pool of clear water where a few fish danced among the rocks and the blades of light filtering through the branches. He was finally alone and had some time to devote to the itch that was tormenting him; between distractions, forgetfulness, and attacks from the Nothing, he had had absolutely no way to check the wound on his side.

  He took off his jacket and laid it beside him, then removed the bandage Dan had made for him. The memory of his friend caught up in the clash with the puppet men made his stomach contract in a painful spasm.

  He squeezed his eyes shut, fearing what he would see once the wound was exposed to the light.

  The bandage was stained with dried blood. He bent down to the side and struggled to see a scar from which small black veins branched out, like bruises in the veins themselves. It itched like never before, and the skin around it showed several abrasions, a sign that he had scratched it very often and vigorously. He decided he would talk to the others about it. He couldn't wait, fearing he would forget again.

  His first thought was to wake Leo. Leo was a boy, so he felt less embarrassed about undressing in front of him, but he imagined that his friend would pay little attention to his concerns, so he approached Kiah. His friend was fast asleep.

  Nico noticed the circles around her tired eyes. For a moment, he felt guilty, but he knew he needed help. “Kiah...” he whispered softly, shaking his friend's shoulder.

  “What's going on? Are you okay? Is it my turn on watch already?” his friend asked, sitting up suddenly and bombarding him with questions. Her eyes were wide open, though still veiled with sleep.

  “I need to show you something,” Nico murmured, lifting his jacket with a slight embarrassment.

  “It's from when that Nerakth hit you in the palace, isn't it?” Kiah concluded with an attentive look, suddenly alert.

  Nico nodded.

  “It looks very strange for a wound,” she said, examining it, then looked up fearfully, staring at Nico in terror. “Was the blade covered in liquid?”

  Nico shook his head, his face troubled. “I don't think so,” he said hesitantly, “although with that light... well, you couldn't see much.”

  Kiah nodded, his eyes narrowed to slits as he stared at the wound.

  “And that's not all,” said Nico as the memories finally came flooding back. “When I woke up, when I took off the visor for the last time, when we disconnected on Captain Fill's ship, I found this wound.”

  Nico shook his head. That wasn't what he meant to say, or was it? Because he always forgot everything, and besides, was that information even real?

  “What? Really? I mean... on your real body?” Leo exclaimed, sitting up and rubbing his sleepy eyes.

  Nico looked around, hoping no one else had woken up. Gareth's shoulders rose and fell at a steady pace, and the princess had her eyes closed and was breathing calmly.

  “Um, I think so,” Nico said hesitantly.

  Leo's face wrinkled as if he had just accidentally bitten into a lemon.

  “I had heard about something like this, but I didn't imagine they had managed to put it into practice,” Kiah whispered.

  Leo's eyes widened so much that for a moment they seemed to pop out of their sockets. “And you knew this game was potentially deadly and you didn't tell us?”

  Leo said, looking at Kiah in amazement.

  “I believe that everything in life should be experienced. It's the basis of the scientific method,” Kiah said dryly.

  “She's crazy,” Leo said, looking at Nico with lips trembling like jelly. “I wasn't sure before, but now it's obvious.”

  “Come on, it's exciting to be among the first beta testers of a technology that hasn't been released yet.”

  “Yes, it was, until I learned that if a huge beast hits me in the head here, I'll wake up dead on the other side.”

  Kiah sighed. “How would you wake up dead? Are you feeling okay?”

  “Really, you're worried about grammar now?” Leo replied, then turned to look at Nico with wide eyes. “Are you serious?”

  Nico laughed, uncertain.

  “Look, it's not grammar, it's semantics. And anyway, what do you want to do? Just quit? I like it here. I'm learning a lot, and you just have to be a little careful, and besides, you can't market a game that kills players... it would be counterproductive. At most, a few bruises, right?” said Kiah, looking at Nico as if seeking confirmation of that hypothesis.

  “But we haven't even done a tutorial,” Leo blurted out.

  “When you were born, did someone give you a tutorial on life? Well, they don't do that here either. It's obvious: it's so vivid.”

  A musical laugh interrupted them. Nico felt a shiver run down his spine. “It's nice to hear you talk, you know.”

  Nico stiffened as he looked at the silhouette of the Princess lying a little further ahead with her back to the fire.

  The Princess sat up.

  “Sorry, Princess...” Kiah muttered awkwardly. “We didn't mean to disturb you,” Kiah said uneasily, “although I'm glad you've recovered.”

  “Don't apologize,” said the princess. Her voice was calm, but her fingers were nervously twisting her cloak. “It's nice to hear you talk about yourselves, I mean without the mask of your characters.”

  Nico's breath caught in his throat, his eyes widened, and his jaw almost dropped to the ground.

  The princess smiled, even though her face was still tired and she had dark circles around her eyes. “I imagine it must be nice to feel a beating heart inside you, the wind on your face, the sun warming your cheeks...”

  “You know we're players, right?” Leo blurted out incredulously.

  “Well, it seems obvious to me,” said the princess.

  “Yes, but I mean,” said Leo, his eyes wide, “can you talk to us about the real us too? And if you can talk about the real us, do you know you're a program?”

  Nadia's face contorted for a moment, her gaze sharp, her lips tight. “Yes, I know I'm part of a game,” she said, stiffening her shoulders with a smile that didn't reach her eyes. “Me and others are, how shall I put it, ‘conscious’...”

  “Amazing, absolutely amazing,” Kiah murmured, her eyes as big as saucers.

  “Excuse me,” Nico began hesitantly, “but if you know it's all a game, why...”

  “Because it's not all a game,” Nadia replied, staring at Nico with her clear eyes.

  “What do you mean?” asked Kiah.

  “Well, you see, the Void isn't something that was already programmed into the game like me or Gareth.” His gaze faded as he stared into the fire. His eyes clouded over as if he were looking at something beyond the flames: "Taynor isn't just a beautiful stronghold in the hills, it's also a command center. From there, my father and I, with the help of a small group of advisors, carefully monitored the system's performance. For example, I have an antivirus system built into my programming."

  Nico exchanged a glance with Leo, trying to keep up.

  “That explains why it was so powerful,” Leo murmured.

  Nadia nodded: “But it's not enough,” she whispered, her shoulders slumping in an almost imperceptible movement.

  “Explain yourself,” Nico whispered.

  “Not long ago, Erebos, a computer virus, came to our attention,” said Nadia, staring into Nico's eyes, clear and blue like a frozen lake.

  “Why are you talking to them about this? What do you hope to achieve?” said a voice behind them.

  “Holy salami!” exclaimed Leo, jumping up. “Is it possible that they designed you to be such a pain in the neck?” he concluded, addressing Gareth and ruffling his hair nervously.

  “I think they should know,” Nadia said coldly.

  Gareth nodded as he sat down by the fire, the flames casting orange lines across his face.

  “It's not just a coding error. Someone... planted this corruption. From within. Or from without.”

  “Great, no sooner said than done. I'm off, bye,” Leo exclaimed ironically.

  “It's not that simple,” Nadia whispered.

  “When has it ever been?” Leo muttered.

  Nico stared at Nadia, confused, then she took a slow breath and murmured, “You gave him access.”

  Nico frowned. “What are you trying to say?”

  “Once the door is open,” she continued, “it can act: read files. Steal passwords. Search for other devices on the network. Erebos was written to self-replicate, it can jump from one computer to another, exploiting flaws in the operating system. And if it's connected to a remote server, it can receive commands, update itself, mutate.”

  Nico didn't know much about programming, but he understood what it meant for something to propagate itself. Nico was reminded of the Nerakth, which multiplied relentlessly when the oily liquid touched someone.

  “So it could...” He paused, uncertain.

  “Spread throughout the world, yes, the real world, I mean. If it hits a network large enough, if it finds a flaw, it could destroy your world, at least as you know it now.”

  A deathly silence fell over the camp. The hot midday sun gave way to the afternoon warmth, and the crackling of the fire was the only sound; even the wind had stopped blowing.

  Nico stared at the flames, searching for meaning. The itch in his side returned, and he blurted out: “Excuse me, Nadia, but if the game had these problems, that is, this virus that was already present before we started playing it... why did the manufacturer send it to us?”

  Nadia looked down: “I have no information about that,” she murmured, her voice tense. “My father and I were only responsible for the internal functioning, checking for errors and system destabilizations.”

  Nico exchanged glances with Kiah; his friend didn't seem convinced either.

  Nadia took a slow breath: “The game system is governed by several programs. Some manage the players' sleep-wake cycles, the changing seasons, NPC interactions... the whole world you see. I'm part of one branch of it.” She shook her head, her face tense: “As for the visors... I don't know who sent them to you. I can only assume that Erebos has found a way to communicate with the outside world.”

  Nico felt a twinge in his stomach. Nadia either didn't know any more than they did, or she didn't want to say.

  Kiah ran a hand through her hair, agitated.

  “But that's not possible...” he exclaimed. “If we were the ones who opened the system to Erebos, how could it have reached other systems? And then there's another thing...” he said, pointing to the head of curly hair. “The note that came in the box with the headset said it didn't need power or the Internet. It seems closed, right? So how did the virus get out?”

  Nico turned to her, struck by the question.

  “I can't tell you how the physical hardware, the headset, works. There are other programs that manage that,” said Nadia, almost annoyed by the question.

  “My father and I are defense programs. Taynor should never have been attacked by the Nothing, by Erebos. Taynor was a stronghold from where antivirus programs like me,” she said in a pained whisper, “protected the game world.”

  She shook her head, tears in her eyes. “We didn't fully understand what Erebos was,” she said more softly. “It got out of control right from the start. And now... if your world is starting to show anomalies, it's possible that there are already active infiltrations.”

  Nico felt a shiver run down his spine.

  Leo looked up as if he had suddenly connected some invisible dots.

  “I heard on the news that in New York... there was chaos because the traffic lights weren't working. Could it be connected?”

  Nico watched Leo closely; his friend had been strangely quiet until then.

  Nadia frowned: “At this point, we can't rule anything out.” Her voice trembled and her eyes met Gareh's, who was staring at the princess. “I don't know your world. I was designed to stay here, with the rules of this system. Someone else will know how to answer these questions.” Then the princess's gaze darted to the side, as if to escape that of the guardian: “But one thing is certain: if Erebos is causing damage in here and at the same time affecting the outside world, perhaps your presence here is not a mistake. You are outsiders. You do not belong to the system, perhaps that could work to our advantage.”

  The princess brought a hand to her temple. Nico saw her stagger. Gareth rushed towards her, but the princess waved her hand in the air, dismissing his help.

  “I'm sorry...” she murmured, “I've just... used up too many resources.”

  She gave a tight smile that didn't reach her eyes: “In some ways, we seem terribly human,” she added, with a crack in her smile, “even though we're not really.”

  Then she turned to Nico: “That wound needs to be checked,” said Nadia. “I have to examine it... but not now. I'm too tired.”

  Nico nodded and, as if wanting to escape from all these revelations, stood up. Gareth announced training for him and Leo.

  They practiced swordplay and target shooting; Nico with a bow, Leo with throwing knives. Gareth seemed unable to relax. Even when he appeared lost in thought, he kept casting worried glances at the princess, who was still asleep.

  In the evening, when the heat of the sun had given way to the damp night breeze, the princess sat up for her evening meal.

  After a frugal meal of bread and cheese, Gareth said he would go on reconnaissance one last time before setting the guard shifts. Then Nadia, the sentient antivirus, called him to her, as her wound needed to be examined.

  [AUTHOR'S NOTE]

  Log updated: the system asks readers to interact with the information just discussed by the group in order to evaluate reactions.

  Log closed: the system observes, evaluates, and considers interactions.