What everyone else has said. Plus:
The One Tree may not be my favorite Chronicles, but it is certainly in the top 3.
However, I always face reading The One Tree with no small amount of trepidation. There are not a lot of fun things happening in this book; it might have been called "The Book Of Woe" for all of the pain and misery that the reader is subjected to if they want to continue their journey.
- Covenant's vulnerability to the venom, which almost cost him his arm
- Covenant's humiliation at the hands of the Elohim
- Losing Covenant to the Elohim's silence
- Exploring in lurid detail the darkest parts of Linden's past
- The maiming of Starfare's Gem
- Linden's sacrifice to save Covenent from Kasreyn
- The deaths of so many Haruchai
- The Haruchai's distrust of Linden
- The Haruchai's withdrawal from service
- And the ultimate defeat at the One Tree
So I would not call The One Tree a fun read. No, I have to gird myself up to read it each time. I have to be in a certain mental state, where I can empathize enough to feel the pain, but not so much that I find the reading to be distasteful.
I can see why the Quest leaving the Land might be a sticking point for some. Well, the archetypal Quest does require the heroes to leave and come back with something. But in the first Chronicles we were treated to seeing the people of the Land fight for the Land; it was part of the Land's beauty. In The One Tree, the people of the Land have become useless in saving themselves, and they are dropped out of the story; they are irrelevant to their own salvation. That's sort of a sad realization. In fact, between that and the Sunbane, it's hard to keep feeling a love for the Land.
As for the Worm and the Creator, I think I have the answer to that, it doesn't daunt me. The Arch of Time is alive; anything alive contains the seeds of it's own destruction; different myths can model the same underlying reality. (
link).
Skipping past everything that's already been said, I would add that Pitchwife emerges in The One Tree as a character to reckon with. At the beginning, he's a curiosity; at the end, he's a necessity. When later in White Gold Weilder he becomes divided against Covenant, this is something that we the reader feel with the most profound dread - and that's only possible because we believe in him so much. Pitchwife is certainly one of Donaldson's greatest creations, and The One Tree is where that character is born.
Mentally, I know that all the pain and sorrow in The One Tree is necessary - necessary for the plot, necessary for the characters, necessary for the reader. White Gold Weilder would not be transcendant if not for The One Tree.
But that doesn't make it fun to read.
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