The Moon of Gomrath by Alan Garner is one of the great fantasy novels - and what raises it so far above the earlier Weirdstone of Brisingamen is its sub-plot about The Old Magic. Its wonderful climax and ending involves the saving of the world by the Old Magic and its liberation 'forever'.
The Old Magic is moon magic and sun magic, and it is blood magic, also, and there lies The Hunter's power and his need. He is from a cruel day of the world. Men have changed since they honoured him.
You keep saying the Old Magic has been woken, said Susan, but if it's as strong as this, how did it ever come to die out?
That is the work of Cadellin, said Albanac, To wizards and their High Magic of thought and spells, the Old Magic was a hindrance, a power without shape or order: so they tried to destroy it. But it would not be destroyed,: it would only sleep...
So there's nothing bad about it at all, said Susan. It just got on the way.
Yes, you may even say that the wizards acted without right. But then, as ages pass, the world changes; so it is true that the Old Magic is wrong fro these times. It does not fit the present scale of good and ill.
But it is more natural than all these spells, said Susan. I think I understand it better than anything here... What does the Hunter do?
Do? He is, Susan: that is enough. There you see the difference between the Old and the High. The High Magic was made with a reason: the Old Magic is a part of things. It is not for any purpose.