The Dragon Hoard

The Dragon Hoard is a fantasy novel, Tanith Lee's first, and a Fractured Fairy Tale retelling the story of Jason and Medea -- kind of.

When Prince Jasleth and Princess Goodness are cursed by a sorceress who wasn't invited to their birthday, their kingdom is threatened with ruin and Jasleth is forced to go and seek his fortune. After several false starts, he joins up with Prince Fearless, who is recruiting heroes for a quest to sail to a distant kingdom and recover the fabled Dragon Hoard.

Tropes included

 * Curse: A significant plot driver.
 * Evil Sorcerer: There are a few, including Stamp-Weed, the appropriately-named Awful, and several others unnamed; there are also several very unpleasant sorceresses.
 * Hair of Gold: Princess Goodness, whose hair is "just the colour of summer sunlight" in the first chapter and "bright golden as a buttercup" in the last.
 * Hands Off My Fluffy: Early, while Jasleth is looking for a quest to join or a monster to slay, he comes across a prince tussling with a two-headed monster, but it turns out that the monster is the prince's pet, they were just playing, and neither appreciates Jasleth's offer of assistance.
 * Happily Ever After: The end states in as many words that everybody lived happily ever after. Well, almost everybody...
 * Hoist By His Own Petard: The fates of most of the villains.
 * How Do You Like Them Apples?: Jasleth gets a (short-lived) job in an apple orchard, hoping to find that one of the apple trees bears magic apples or is an enchanted princess. Much later, he encounters a grove of magic fruit trees that grow fruit made of gold; the varieties mentioned include oranges, plums, damsons and, inevitably, apples.
 * Impossible Task: The tasks the heroes are required to do before retrieving the Hoard: taming a pair of wild, fire-breathing horses; emptying a lake into a jug; and bringing back a magic orange from the grove at the far end of the kingdom in less than a day. (Not to mention, after all that they still have to deal with the dragon.)
 * Involuntary Shapeshifting: Jasleth is cursed to turn into a raven for one hour a day -- and it's a different hour every day, at random, so he never knows when it's about to happen until it does.
 * In Which a Trope Is Described: The chapter headings
 * Love At First Sight: Multiple examples, most notably Prince Jasleth and Princess Jadelli.
 * Magic Mirror: Maligna has one, with the standard feature set: it talks, answers questions like "Who is the fairest of them all?", and can show events occurring distant places.
 * Meaningful Name: Plenty -- King August, King Purple, Prince Fearless, Princess Goodness, the sorceress Maligna, the sorcerer Awful, ...
 * Mobile Shrubbery: After the heroes' ship is captured by Queen Emeraldis, Jasleth the raven sneaks aboard disguised in a large seashell.
 * One Scene, Two Monologues: When Jasleth and Fearless are discussing what to do about the dragon that guards the hoard.
 * Our Dragons Are Different: It has several wildly different types of dragon, including (although only in the Story Within a Story) one that's allergic to gold.
 * Plucky Comic Relief: Prince Sillius
 * Purely Aesthetic Era: The Dragon Hoard has a non-specifically-medieval European setting, with references to modern concepts like dentists and deckchairs as dictated by the Rule of Funny.
 * The Quest: To retrieve the Dragon Hoard.
 * Rags to Royalty: The royalty-to-rags-to-royalty version for Jasleth's family.
 * Ravens and Crows: see above, under Involuntary Shapeshifting
 * Revenge SVP: Maligna's motivation for messing with Jasleth's family.
 * Standard Hero Reward: When Prince Fearless is recruiting heroes to his quest for the Dragon Hoard, his father insists on offering his daughter's hand in marriage as a prize for the hero who does the most during the quest. Fearless, who is keenly aware that his sister is a Royal Brat, tries unsuccessfully to dissuade him, and actually apologises to the "winning" hero. (Fortunately, it turns out there is a prince who loves her despite her faults, thus allowing the winner an excuse to nobly relinquish his claim.)
 * Story Within a Story: When the heroes are forced by the sorcerer Awful to tell a story or perish.
 * Taken for Granite: The heroes come across an island where everything has been turned to stone by an evil sorceress.
 * Talking Animal: Every animal in The Dragon Hoard.
 * That Cloud Looks Like...: Jasleth, faced with a group of men with hostile intent, attempts to distract them by engaging them in a conversation about the shape of a cloud. It doesn't work.
 * Thicker Than Water: Jasleth resorts to several deceptions to secure a place on the Hoard Quest; when the other questors find out, they forgive him because he only did it to help his family.
 * Treacherous Advisor: The sorceress Maligna arranges to become one to the heroes in order to prevent their quest from succeeding.
 * Who Will Bell the Cat: Jasleth and other rowers hide to await the sea monster and attack it, but when it actually appears, they nervously offer each other the chance to do it.