Celydonn is the setting of two Fantasy trilogies by Teresa Edgerton: the Green Lion Trilogy and the Celydonn trilogy. It can be thought of as an Alternate Universe mediaeval Britain in which magic is real, but it isn't a straight Alternate History setting.
For example, the setting as introduced in Child of Saturn has recognizable analogues to various figures of the King Arthur legend - the kingmaker wizard Glastyn, the High King and his queen, the knights of the king's Order of St. Mark - but with significant changes to the characters and a different culture and history.
The Green Lion Trilogy consists of:
- Child of Saturn
- The Moon in Hiding
- The Work of the Sun
The titles of the Green Lion trilogy (including that of the trilogy itself) are references to alchemy. (The king's wizard, who is the female protagonist, is an alchemist, as was her predecessor. They both pursue alchemy not for the sake of becoming rich, since it's simply not cost effective, but for how it tries and purifies the one who seeks wisdom by its study.)
The Celydonn trilogy, a sequel trilogy to the Green Lion trilogy, focusing on a different subset of the original trilogy's cast, consists of:
- The Castle of the Silver Wheel
- The Grail and the Ring
- The Moon and the Thorn
- Alien Sky: In The Grail and the Ring, the Inner Celydonn's version of Tir Gwyngelli currently has three moons. Its neighbours have differing numbers of moons.
- Altar the Speed
- Alternate Universe: the Inner Celydonn
- Arranged Marriage
- Artifact of Doom: the titular grail in The Grail and the Ring
- Bigger on the Inside
- Bizarrchitecture
- Can Not Tell a Lie: one of Prince Tryffin's geasa, along with things such as 'never take iron from the dead'.
- Chess with Death
- Childhood Marriage Promise: subverted in The Castle of the Silver Wheel
- Curse
- Evil Mentor
- The Fair Folk
- Full Boar Action
- Functional Magic
- Innocent Cohabitation
- The Jailbait Wait
- King Arthur: the names are changed, however, and the personal relationships play out very differently - the queen is faithful to her husband, and has better sense than he does about some things.
- The Kingdom
- Kissing Cousins
- Knight in Shining Armor
- Laser-Guided Amnesia
- Mad Scientist Laboratory
- Mistaken for Cheating
- Older Than They Look
- Our Werewolves Are Different
- Plot Coupon: the titular grail from The Grail and the Ring
- Prophecy Twist
- Relationship Upgrade
- Religion of Evil: the Black Canons (the villains formerly known as the cult of Cerridwen)
- Royal Brat: Calchas
- Royal Blood
- Royally Screwed-Up: the Lords of Mochdreff
- Set Right What Once Went Wrong: the main plot of The Grail and the Ring
- Speak Now or Forever Hold Your Peace
- Standard Royal Court
- Time Travel
- The Unfavourite
- Visions of Another Self
- The Watcher: Dame Ceinwen
- Wedding Deadline
- The Wise Prince: Tryffin, in the second trilogy.
- Zombie Apocalypse