Based on patronustrip armory and weapons post on Tumblr.

Broadsword - Fryst Hjarte

Elsa was in a pinch. Anna's birthday was in a week and she had no idea what to give to her favorite knight. It was the downside of being royalty; she already has everything (ok, so most of them were gifts from Elsa throughout the years). She thought about giving her a new sword, as Anna had carved "Winterstorm" for her as a present in her last birthday… but she already had "Winterkiss"… and "Ren Is"… and "Kald" and "Vinter"…

"Maybe a new armor? No, she already ordered one the other day… a new horse? Come on Elsa, she already has three! A dress? Yeah right," Elsa laughs at her absurd dress idea.

Last time Anna was given a dress was when a "suitor" tried to "win" her favor. A chauvinist pig that thought too high of himself. The bastard really thought that all the rumors about her sister's abilities were just those… rumors. He wasn't laughing when Anna chopped of his arm with "Winterkiss" after a particular insulting comment about women's place in this "world of men". Anna threw the horrid dress to him to use it as a bandage and kicked him out threatening him with losing his other arm.

Elsa kept on pacing back and forth in her room. What to give her? WHAT TO GIVE HER?

She stopped. There was noise outside her window. She approaches and looks outside. Anna was sparring with five of their men using "Kald" and "Vinter"… No… she was sparing with eight, but three were already out of commission. Watching her sister move with the swords in her hands was like watching a deadly dance. A beautiful deadly dance. The five men left attacked at the same time. Fools, as if numbers would win against her sister. Elsa had seen her battle greater numbers all by herself. True, Anna didn't get out unscratched from those battles but the fact that she managed to win, alone, was enough.

Elsa saw Anna grin before she started moving, her eyes shining with bloodlust. Elsa loved when Anna had that look in her eyes. She almost felt bad for the guards sparring with her… almost. The battle was over too quickly for Elsa's taste. That meant that those guards weren't good enough and that she would need to organize a new Royal Guard recruitment soon. Anna sheathed "Kald" and started using "Viter" to poke the fallen men, obviously teasing them for being so weak.

The captain, a 50 year old man and the only one in the guard that Anna respected, approached. That man had being the one to give Anna her first fencing lesson when she was a child. They talked about something. Elsa couldn't listen but by, her sister's expression, it wasn't something good. Anna ended the conversation hitting the captain in the face with "Vinter's" hilt and walking away. Elsa grew curious of what had happened and so she told Kai to summon him to the throne room.

The man explained what had happened, a hint of fear in his voice (being alone with the "Ice Queen" was not something to be taken light). Elsa laughed out loud with the story. Oh her sister! She was to turn 19 years in a week and still acted like a child. She dismissed the man after some more small talk. She told Kai to add a cup of the finest wine the castle had in the man's meal that night. He deserved the reward. Thanks to him, Elsa now knew what to give her sister as a present.

A week passed and Anna's birthday arrived.

All of Arendelle's closest trade partners and allies were present at the ball, waiting for the Queen and Princess to be announced.

Elsa entered the ballroom in one of her long ice dresses. Her hair on a braid across her back and her bangs swiped back. All regal and gorgeous… and dangerous. As Elsa reached her throne Kai announced Anna. She entered clad in her finest knight clothes. She wore breaches, long sleeved tunic, thick leather gloves, cape, and boots. "Winterkiss" hanging from her belt, her hair lose over her back with a tiny braid over her right ear. For a 19 year old girl with a small frame, she looked intimidating. She positioned herself at Elsa's right side. Not even during her birthday would she stop protecting her beloved sister and Queen.

Elsa gave a few welcoming words, congratulated her lovely Anna for her birthday and the celebrations continued. As usual, no men approached to ask for a dance with either of the sisters. Last time one had dared to request one from Elsa, he had soon found the tip of "Winterkiss" against his throat, a drop of blood falling slowly from where the sword touched. They did approach to congratulate her highness and give her the correspondent gift. A cape made of the finest Arabian fabrics, golden pins engraved with Arendelle's family crest, a new saddle for her horse… Anna was not amused.

If something… she was bored…

Elsa thought this the best moment to bring out her gift.

She ordered the musicians to stop playing and ordered Kai to bring it out. The captain appeared with a long wooden box with intricate yet beautiful designs. Elsa led her sister to the center of the room so everyone could see. Anna opened the box and smiled, she turned and hugged and kissed her sister's cheek lingering a little more than usual. Elsa also smiled, that kiss that seemed so innocent to others meant something entirely different for the Arendelle royals. It promised one heated night ahead of them. The proper way for Anna to thank Elsa for this marvelous gift.

Anna took it out of the box for all to see. It was a two hand broadsword, nearly as big as her. The blade was made with Elsa's ice; the hilt was surrounded with the finest leather and had a jewel in the middle. Anna recognized it as Elsa's pin, the one she wore during her coronation. People started to whisper… "isn't the sword to big?" "Will she even be able to use it?" "She's too small for that sword, such a pity" "that sword will end up as decor in the library I bet."

"ENOUGH!" Anna was pissed, "So you think this sword my sister just gave me will be wasted on me? Bring your best men! I'll prove here and now that you fools underestimate me!" Elsa walked back to her throne slowly, amused smile on her face. With Anna around things were never dull.

"You heard my sister," said Elsa sitting down, "each of you, bring your best men right this instant."

Within minutes 6 soldiers from different realms were standing in the middle of the room with Anna. They were all taller and heavier than her. The knight had a little wicked smile on her face, her eyes had darkened dangerously.

"Start," commanded the Queen. Within minutes 6 lifeless bodies were scattered across the ball room, Anna standing tall among them, covered in their blood, breathing heavily from the thrill of the fight.

The bodies were removed and the ball ended. Kai laughed low thinking of the fit Gerda would throw in the morning when she saw what the maids would have to clean.

"I deeply apologize for my behavior and comments from a week ago your Highness," says the captain going down on his knees in front of Anna, "I have never being so wrong in my entire life. You are no longer that little girl holding her first practice sword. You are a full-fledged warrior so here and now I, once again, pledge my faithful service to you and her Majesty until the end of my days." After that the captain rises and leaves, leaving the sisters alone.

"I'm glad to know you liked your gift," says Elsa hugging Anna from behind.

"It's an excellent sword 'My Queen'", answers Anna leaning on Elsa and lifting the sword to appreciate it from different angles, blood still dripping from the blade, "does it have a name?"

"Fryst Hjarte," says Elsa, "it means 'Frozen Heart'. I named it like that because, as you could see moments ago, it's unforgiving with anyone that crosses its path. Certain death in the hands of its rightful bearer," explained the Queen, "the best only for you, my love. Happy birthday"

Elsa tilts Anna's head to the side and kisses her lips.

"A happy birthday indeed," says Anna.

A little something that has being in my head for a while. Again, the name of the swords can be found in patronustrip blog on Tumblr … First time writing a Dark AU… I might write one again… it was fun…