The Fire-Bird, the Horse of Power, and the Princess Vasilissa is a Russian Fairy Tale collected by Alexander Afanasyev in Narodnye russkie skazki.
A Tsar had an archer serving him who had a horse of power. One day, as he rode in the forest, he saw a marvelous feather which he knew must have been shed by the legendary Firebird. The horse warned him not to pick it up, but he did anyway, figuring the tsar would reward him. But the tsar demanded that he bring back the whole bird or lose his head.
Terrified, he asked the horse what to do, and on its advice, he requested that a hundred sacks of maize be spread over fields at night. At dawn, the firebird arrived, and the archer captured it with the aid of his horse. But no sooner had he returned with his prize than the tsar sent him on another quest: to go to the very edge of the world and bring back Princess Vasilissa for his bride. At the horse's advice, the archer asked for a silver tent with a golden roof, and victuals for the journey. He rode to her land, set up the tent, and spread out the food. Curious, the princess approached, and the archer invited her to eat and drink. She drank and fell asleep, and he put her on the horse and rode back.
Vasilissa, finding that she had been carried off to be the bride of the old and greedy tsar, refused to marry him without her wedding dress, which was still in her own country and hidden under the sea besides. The tsar again dispatched the archer, who rode his magical horse back to the edge of the world. On the shore, the horse waited until it could get between an enormous lobster and the sea; then it set its foot on its tail and did not let it go until it agreed to bring up the wedding dress.
When he returned with the dress, Vasilissa still would not wed until the archer had been boiled alive as punishment for abducting her. Terrified, he asked to see his horse one last time, but the horse seemed pleased with how things were going and advised him to submit. The princess waved her hand over the boiling cauldron, and the archer immediately plunged in and came out unharmed and even handsomer than before. Seeing this, the tsar jumped in as well, but he boiled to death. The archer became tsar in his place, married Princess Vasilissa and had a fine stable built for the horse, for he had learned the lesson of gratitude.
Full text here
and here. Compare "Tsarevitch Ivan, the Fire Bird and the Gray Wolf". This story also has some notable similarities to The Humpbacked Horse (aka The Magic Pony)
Tropes included:
- Abduction Is Love: Vasilissa falls for the archer even after he lures her in, abducts her, and gives her as a bride to another man.
- Ambiguous Situation: Vasilissa apparently does something to the cauldron just before the archer jumps in, but not even the narrator knows for certain.
- Attention Deficit... Ooh, Shiny!: All because the feather was so golden.
- Beauty Equals Goodness: The archer is young and handsome and therefore good. The tsar is old and ugly and therefore evil.
- Cool Horse: The Horse of Power.
- Cue the Sun: The birds arrive at dawn.
- Don't Touch It, You Idiot!: The horse warns the archer to leave the feather alone, but he doesn't listen.
- Dude, Where's My Respect?: The tsar gives the archer and his horse nothing but further demands, no matter what they accomplish for him. When the archer becomes tsar, he makes sure to reward his horse for everything it has done for him.
- Hypercompetent Sidekick: Let's face it; the horse does most of the work.
- Impossible Task: Every quest
- It Was a Gift: How the archer's problems started.
- Jerkass Victim: The ungrateful tsar dies a horrible death, but we don't feel too sorry for him.
- Living MacGuffin: The king orders the archer to bring princess Vasilissa as a bride for him.
- Love Triangle: The king, the princess, and the archer
- Nameless Narrative: No one is named in this story except the princess.
- Offered the Crown: The ending
- The Quest: Three of them.
- Royal Brat: The tsar.
- Rule of Three: Three quests. However, there are four Impossible Tasks, and the fourth instance breaks the pattern. The first three times the horse tells the archer that things are bad but they could be worse; the fourth time he says that things are actually better than he expected.
- Sapient Steed: The titular horse of power not only can talk but also is smarter than its owner.
- Self-Disposing Villain: The tsar conveniently dispatches himself at the end of the story, though it's implied some (forgivable) sorcery or deception on Vasilissa's part was involved.
- Talking Animal: The archer's horse is constantly giving him sage advice and comforting words.
- Ungrateful Bastard: The tsar. His response to the archer's doing something nice for him is: "Carry out several increasingly impressive and impossible tasks for me, or you will be beheaded."
