It is quite cool today for the approaching summer. It has rained all night and even now the air is still damp and water has accumulated everywhere. Mary has given up jumping over the puddles of water, her feet are already wet. Shivering, she arrives at Gaius' chamber. The old man is just sitting up in bed, contorted with pain, "Ah...you're here early today."

Mary comes over to him, "I couldn't make part of the rounds. Everywhere people are trying to save their belongings from the water. It hit the houses along the river especially hard."

Gaius nods, "I heard. Arthur went with some knights to help. You look like you didn't stay completely dry either."

Mary looks down at herself. The hem of her dress is wet and dirty. Her shoes have a hole in the sole; she should have taken them to the shoemaker a long time ago. She sits down and takes off her boots. Gaius raises an eyebrow when he sees her soaking socks. "Mary, you'll catch your death." groaning, he stands up.

Mary asks worriedly, "Are you not feeling well?"

"Oh the dampness isn't doing my old bones any good. Take off your wet clothes...I have some dry things for you here somewhere."

Mary disappears behind the screen and strips off her skirt. She also takes off her socks and now stands barefoot on the cold stone floor. Gaius puts some fresh socks over the room divider for her and a turquoise dress. Mary looks at it closely. The fabric is fine and it seems as if the dress once belonged to a noble lady. It fits Mary like a glove. She puts her woolen scarf over her shoulders so that she will be a little warmer. When she comes out from behind the screen, Gaius looks at her: "Wonderful. The dress fits. I almost forgot."

Merlin just enters, also quite wet. Astonished by the picture he sees, he stops in the doorway.

Mary asks Gaius, "Where did you get such a beautiful dress?"

The physician sits down heavily on a chair, "Oh, it was a gift once...but I don't remember why or where from."

Merlin says, "The color suits you, Mary." Then turning to Gaius, "I'm going to change and then leave right away. Arthur wants a bath ready in his room and a fire burning when he gets back."

Mary and Gaius have been making tinctures, reading, and bundling herbs in the physician's chambers all day. A stew is simmering over the fire and Mary is about to set the table when there is a knock at the door and a guard looks in, "The king is asking for you."

Mary and Gaius instantly make their way to the throne room where Uther, Arthur and some men of the council are already waiting for them. As they stand before him Uther says, "I want you to go downstairs to the servants' quarters and see what is happening there. More than a quarter of the staff could not come to work today."

Mary and Gaius bow their heads and immediately set off. In the lower part of the castle there are small chambers for the servants who do not have their own cottages in the lower village, like Gwen or Mary. It also has a small kitchen there for the servants, along with a watering hole where they can wash. Mary is rarely down here. As soon as they get there, a maid rushes up to them, "Quick, please. She's not well at all." She pulls Gaius and Mary with her into one of the tiny chambers where there is a bed and a small table. In the bed lies a young woman. She is pale and has beads of sweat on her forehead. Gaius feels her pulse and Mary observes that the woman is having trouble breathing. Mary and Gaius exchange a glance. It is clear to both of them that this is poisoning. Mary notices that one of the woman's feet is quite swollen. When she examines it more closely, she discovers three small holes that almost look like a snake bite. She quickly shows these to Gaius and he frowns. Around the wounds, the skin is already turning grayish.

Gaius stretches and asks the maid who led them here, "How many are sick? And do they all have the same symptoms?"

The maid, whose name is Agnes, replies, "There are probably two dozen sick. From the kitchenboy, to the chambermaid, to the stableboy from every part of the castle."

Gaius looks at Mary, "Best we split up. Give everyone something for the fever and something to help them breathe. We need to find out where it's coming from." Mary nods and follows another maid to the rest of the sick.

Tired, exhausted, and hypothermic, they both arrive back at the physician's chamber two hours later. Merlin is sitting by the fire and looks up as they enter. He gets up and immediately ladles them two bowls full of stew, which he has kept nice and warm, at the edge of the fire. Mary and Gaius gratefully take the warm bowls in their hands. Merlin asks, "So, what is it? A cold or some other plague?"

Gaius shakes his head, "I'm afraid it's something much worse than a cold." He takes a spoonful of the warming soup. Merlin who has already eaten sits down with them after putting some more wood on the fire.

Mary says, "They all had the bite wounds, Gaius."
"Yes, the same with my patients."

"They look like they were made by a snake, if it weren't for the third little hole." Gaius nods gravely. Mary asks, "Do you know what it's from?"

"I have a guess. Let's finish eating and then I'll see if I can remember what book it's written in."

A little later they are both poring over different books and Merlin is watching them. It's getting late when Gaius finally calls out, "Here, I got it." He points to a picture in the book that shows the exact bite with three bite wounds applied in a triangle.

Mary confirms, "That's exactly what it looked like on each of the sick people."

Gaius sighs, "This is bad. Very bad. The bite is from an shimmer-viper. They're magical creatures, which have a third in their lower jaw in addition to the top two poison fangs."

"Where do they come from? And how do we get rid of them?"

"For once my child, I have no idea." Speechless, the three stare at the picture of the delicate snake in the book.

Early the next morning, Merlin wakes up. He hasn't been sleeping well and has been dreaming about the magical snake over and over again. He rubs sleep out of his eyes and stumbles down the stairs to the physicians room. Gaius is about to leave, but he turns to Merlin, "Merlin, I need to go to the servants' quarters again. During the night, six of the sick have already died. When you have had breakfast, go to the prince and warn him about the snakes. Everyone here in the castle must stay away from the stone walls." Merlin looks at him questioningly. Gaius explains, "The shimmer-vipers like it cool and damp. They usually hole up in stone walls. I need to check on the sick and I'll go straight to the king later. Don't wake Mary...she only fell asleep a short time ago. She will go through the castle later and look for the hiding places of the Snakes. There must be several with all the bites. As they shed their skin you often find glistening scales near their lairs. Mostly near the ground, that's why all the bites so far are in the calves or feet." Merlin looks to the sleeping girl in front of the fire and nods.

An hour later, Mary is walking through all the aisles. She started at the top and is slowly working her way down floor by floor. At the very bottom of the castle is where most of the vipers will dwell, it's the most humid there. She is walking through the corridors where the royal family has their rooms, when Merlin agitatedly turns a corner. When he sees her he calls out, "Mary, quick...the prince is not well."

As quickly as she can, Mary hurries after him. Arthur lies pale in his bed. When she addresses him, he opens his eyes and looks at her with a glazed expression. Mary asks, "Arthur, may I examine you? Gaius isn't here right now." Exhausted, the prince nods. Merlin watches Mary with a worried look. After a moment, she looks up at him, "Merlin, the prince was bitten by a shimmer-viper. I'm sorry."

Merlin shakes his head, "No, it can't be...it is my destiny to protect him."

They both startle as Gwen rushes into Arthur's chamber and says in a panic, "Please, Morgana is not well. Can someone help me?"

Merlin and Mary rush with her to Morgana's chambers. The king's ward is lying on the floor and Gwen hastily says, "She suddenly collapsed. I couldn't do anything."

Merlin bends down and lifts Morgana up. Then he gently lays her on her bed. Mary examines her briefly, although she already knows that Lady Morgana has also been bitten by a shimmer-viper. After explaining to Gwen how to cool Morgana, she walks out of the room and leans against the wall in the hallway. She closes her eyes for a moment and takes a shaky breath. She feels powerless and desperate. Arthur and Morgana are going to die.

"There must be a way to save them."

Mary opens her eyes and looks at Merlin, "I have never seen Gaius so perplexed. I will go to him and tell him about the prince and Morgana."

"I'll go to Arthur again, and then I'll check the library. See if I can find anything there."

Mary comes quietly and slowly back into the physician's chamber. Gaius is sitting at one of his many books and notices how depressed she is, "Mary, what happened? Did you find the vipers' hiding places?"

Mary replies, "No, but they have now bitten Arthur and Morgana as well. We have to get the king to safety somehow."
Gaius looks at his book again, "It's too late for that. When I came back from the servants, the king was in his bed...he was bitten too."

Mary can't believe what she's hearing, "You mean...you mean Camelot is doomed? There must be a way to save everyone?"

"I don't know how...I'm sorry Mary."
Mary feels dizzy and has to hold onto the edge of the table. Gaius looks at her with concern. Mary draws in a breath and says, "I need to get some fresh air...Just a minute." She turns and hurries out of the room.

Merlin walks past the library and the dungeon in that time, on to the dragon's cave. "Hello? As before, I come to say goodbye...My destiny will not be fulfilled...Camelot will perish." He just turns around again and is about to leave when he hears the familiar flapping of the dragon's wings, which lands on the rock behind him.

"What do you mean Camelot will fall?"

"Arthur, Morgana, and Uther were all bitten by shimmer-vipers. According to Gaius, there is no way to save them. Nowhere in his clever books is there anything about a cure for this. Many servants have already died."
The dragon tilts his head and looks at the warlock, "Mmh...shimmer-vipers...mean animals. They spring from the Old Religion, like you and me."

"Yes, I know that...but how do we get rid of them?"

"Well...snakes like it damp and cool..."

Merlin rolles his eyes, "I don't have much time. For once, can you not speak in riddles?"

"Well, the opposite would drive the snakes away. It would simply have to be magical as well, like them. The solution to this is right in front of your eyes." The dragon looks at Merlin out of his big yellow eyes. Merlin looks at him as well and hesitantly asks, "You mean...you...you can drive the vipers away?"

"Well, it's not quite that simple. To be able to drive them away I have to give you from my innermost fire. It's not that easy for me and we need a vessel for you to catch it in. You know, my heat is hotter and more dangerous than any fire or embers. The vessel must be made resistant by magic."

Merlin looks at the big dragon gratefully, "I'll be back soon...don't hide again." He runs up the stairs and on into Gaius' chamber. The physician is startled as he rushes in, "Merlin, my old heart can't take it when you come in like that. What's the matter?"
"I need a vessel...preferably the cooking pot...Thank you!" Merlin snatches the pot from the fire and takes it to his room. There he pulls out the spell book and flips through it until, in the back of the book, where the stronger and heavier spells are, he finds the right spell. "Dracafyrswiþ!" Merlin's eyes light up golden and the pot turns glowing red for a brief moment before changing back to its dark color. Frowning, he contemplates his work, "That's it? I hope it lives up to its promise."

Only when he takes the pot in his hand and stands up does he realize how much strength the spell has cost him. He has to support himself briefly with one hand on the bed in order not to lose his balance.

Swaying slightly, he passes Gaius again and gets to the door. The physician asks, "What are you going to do with that? Are you okay?"
Merlin nods, "Yes, everything is fine. Where's Mary?"

"She needed to get some fresh air. Do you know yet that Arthur, Morgana, and Uther were all bitten?"

"I knew about Arthur and Morgana...but Uther...Keep searching for a cure. I'm not giving up yet, and I'm going to get rid of those pesky snakes first."

Gaius just looks after him shaking his head. "Finding a cure...what does he think I'm doing here."

Merlin arrives back at the dragon, out of breath. The latter grins at him and says, "I see...that spell wasn't easy."

"Well, easy it was...I only had to cast it once, but I feel like my wrung out shirt after the wash for that. I need to sit down for a minute."

"Just once, you say? That shows how powerful you actually are. Every other sorcerer has to practice for months if not years for that spell. You are getting stronger young warlock."

Merlin waves it off, "Fill the pot with your fire and tell me how to proceed."

The dragon sinks one of his claws deep into his flesh. Merlin watches him in amazement. The dragon says, "I told you it wasn't easy for me. Let's not even talk about the pain. Annoying beasts these snakes." When the dragon pulls out his claw again, it is dipped in bright orange liquid. He holds the claw over the pot and the liquid gathers into a large drop that falls into the pot. Merlin can feel the heat coming off of it. Merlin sees the wound in the dragon's chest and asks, "Will you heal?"
"Yes young warlock. Do not worry about it. You must take the heat in the pot to the Highest Tower in Camelot and pour it into the stone wall there. The heat will spread throughout the castle and drive away the vipers. My Inner Fire will work for some time, so they won't come back. However, you must be careful...the snakes will know what you are up to and will want to stop you. Even you are not immune to their poison!"
"What helps against the poison? Do you have a solution for me there too?"

The dragon considers for a brief moment: "Well, I know that unicorn tears have a healing effect against it."

Merlin gets to his feet and leans against the wall, "Great...now where am I going to get a unicorn?"
"That's not my problem...they like quiet and magical places...good luck young warlock!"

The dragon rises and flies into the air.

Merlin exhales once with a snort, then grabs the cauldron of charged heat and sets off, "Well, sure, you see unicorns every day and that I have to go up to the highest tower was obvious. Why can't the solution be simple...turn over a stone, for example...or carry a bundle of straw into the castle..." From far above, Merlin can hear the dragon laughing.

When Merlin finally arrives at the Supreme Tower, he looks out the window and sees the nearby forest. There he will have to look for a unicorn next. Slowly, he tilts the pot and lets the heat seep into the stone wall. Suddenly, a sharp pain runs through his left ankle and he looks down at himself. He can just make out a white glittering snake disappearing into the wall. Merlin groans and almost drops the pot. He drops to his knees and continues emptying the heat. He must let it all flow into the masonry, and afterward, by all means, search the forest for a unicorn. He must not give up. He is the only one who knows what must be done and he must not give up. Finally the last drop flows into the stone. Merlin leaves the pot and drags himself with great effort to the stairs and out of the castle. The left side of his body hurts and it becomes increasingly difficult for him to breathe.

When he arrives at the edge of the forest, he trembles under the strain and the rising fever. He leans against a tree and tries to channel his magic inside to counteract the poison. He succeeds only to a certain extent, but he feels he can breathe a little better. His thoughts want to sink into the darkness of unconsciousness, but Merlin resists. Groaning, he stands up.

"Merlin?" He wants to laugh in relief when he hears Mary's voice. But his condition won't let him. His eyes, clouded with poison, search for her. Suddenly he notices her putting her arm under his and supporting him. "Merlin, you're sick...what are you doing out here?"

Merlin gasps, "No time...unicorn tears...heal..."

"Unicorn tears? You mean unicorn tears heal snake bite? Where can we get a unicorn?"

Merlin takes a step into the forest, "Magical...and...quiet place."

Mary tries to stop him, "Merlin, you can't go any further. I'll leave you here and get help."
Merlin weakly shakes his head, "No...your quiet place...I may be able to...by magic...aah." Merlin slumps down in agony.

Exasperated, Mary says, "It's still quite a ways to my sanctuary...you'll never make it..."
The young man claws at her forearm, "Please...otherwise all...is lost. I just need to...collect...for a moment." Merlin closes his eyes again and concentrates on his magic. He can only feel it faintly, and he notices how it only gives a flickering response. Suddenly he feels something in the palm of his hand and his magic flares up once more. As if he could refuel, he feels the magic flow through his body and gather at the site of the bite. The pulsing poison is somewhat inhibited by this and Merlin opens his eyes. In his hand is Mary's necklace. She looks at him with concern, "Does this help?"

Merlin nods, "Thank you! But I don't know for how long I can maintain my condition..."
"I'll help you!" Courageously, Mary makes her way through the thicket of the forrest, still supporting Merlin at her side.

Arriving at the small waterfall, Merlin drops to his knees and, as if guided by an invisible hand, dips his hands, with the chain in one, into the cool water. He breathes a sigh of relief as he feels the magic of the surroundings. It gives him support and strength. Mary watches him closely. Pieps the little magic raven curiously comes closer. Merlin smiles: "Well, little friend? You sure made something of the surroundings here!" The waterfall is gushing vigorously and flowers are blooming all around in all colors. The bushes and trees are a lush green and all kinds of animals can be spotted everywhere.

Mary asks, "And how do we get to a unicorn?"

Merlin wearily lies down in the grass, "I have no idea. Pieps...do you...have an idea?" Mary notices Merlin threatening to pass out, "Merlin, you have to stay with me. I have no idea what to do!"

Merlin, with his last ounce of strength, pulls a small vial from his jacket pocket, which he had packed earlier in the castle, "Here, catch the unicorn tears in here. But remember...the magical...creature must...give it to you...willingly..." groaning, Merlin lays his head on the grass, "I'm...sorry..." Mary kneels down in the grass next to Merlin, who has fainted. She takes her necklace from his hand and puts it back on. Frantically, she looks around: "And how am I supposed to get to a unicorn now?" Her courage leaves her and she desperatly puts her face in her hands.

It doesn't take long and Mary hears soft footsteps coming closer. When something gently nudges her, she dares to look up. She gasps in surprise when she sees a white, beautiful unicorn standing in front of her. The purity of the creature takes her breath away and she feels her necklace vibrate and the stone warm up as well. Hesitantly, she reaches out her hand to the animal's muzzle: "You are beautiful! You are heaven sent...how lucky for me you're here."

The unicorn looks at her from alert eyes that seem to peer all the way into her soul. "It is not luck...the young warlock has called for me. The water has carried his desire for help to me."

Mary tears her eyes open in surprise, "You can speak! But how is that possible..."

"We speak only to those whose hearts are pure. I see you are a helpful person who puts your own needs behind. Merlin is very lucky to have you as his friend. He will need friends on his difficult path, but friends who voluntarily stay in the background."

Mary has tears streaming down her face, "Please, Merlin is dying...and so are many others in the castle. We need your help."

The unicorn lowers its head and Mary watches as a few tears drip from its brown eyes onto the snakebite in Merlin's foot. Then the magical creature turns back to Mary and says, "I give you my tears to make the people of Camelot well. Dilute them with water so that there is enough for everyone." Mary catches the tears in the small vial and then puts the cork back on. She lovingly strokes the unicorn's mane, "Thank you so much you wonderful creature. I will never forget this!"

The unicorn turns away and says, "Take care Mary...maybe we will meet again."

"Was that...a unicorn?" Mary hears Merlin's voice and she looks down at him. Astonished, he looks at her. Mary smiles and says, "Yes! You called it over the water to help you. And did you know that unicorns can talk?"

"That doesn't surprise me...dragons talk too." Seeing Mary's aghast look, Merlin quickly says, "Well...I read that somewhere. Do you have the tears?" Mary holds up the vial, "Yes, let's hurry back. I don't think we have much time."

Merlin grimaces as he stands up, "I'll try to keep up with you as best I can. The poison seems to need some time to completely disappear from my body."

Three days later, all of the poisoned are feeling much better. The king goes back to his duties in council and ruling. Arthur is able to rush Merlin around again and the servant has his sarcastic and sassy sayings ready to counter again.

Mary sits with Gaius and draws a unicorn on one of the parchments. Gaius looks over her shoulder and says, "That creature made an impression on you."

"It was absolutely the most beautiful thing I've ever seen."

"Yes, you are lucky to have seen one. And then it talked to you. How's Merlin doing?"
"I think fine again."

"He needs your friendship and you need his!"

Mary looks at Gaius, "Yes, the unicorn said something similar. I need some more time. Come, let us bundle the dry herbs. Does it also seem to you that it's much warmer in here than usual? The herbs are drying faster than ever and we don't need a fire...the cooking pot is different too. It doesn't get hot at all when it's over the fire."

Gaius raises his eyebrows, "Yeah, now that you mention it...no idea what Merlin did with it."