The Sword of Ice and Fire — John Matthews

An exciting re-imagining of the early years of the boy who would become King Arthur. John Matthews has conceived a quartet of books under the title Red Dragon Rising, of which this is the first volume.
We meet Arthur, Merlin, the Questing Beast, the Green Knight and the mysterious Nine women who rule the castle of Avalon, with its ever-shifting rooms and prophetic bronze mirror. There are horrific enemies such as Amangons and the hideous Fir Bolg. And stalwart companions in the shape of the four Eldest: the shape-shifting Salmon, Stag, Eagle and Blackbird.
And there is Mabon, the shining golden boy-god, whom Arthur and his companions must rescue from an underground dungeon which quenches his powers.
He must also achieve the four Hallows of Albion, of which gaining the Sword of Ice and Fire is the first quest.