Halved

I dont think you're quite right about the Driver's story.

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I think the implication of it is that the missing Sun of the Reach is murdered by the messenger using "well seeds", and the gleaming gold that Old Tom saw inside the well is the Reach's sun (or rather, it's corpse).
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As for the Halved. Spoiler for Well of wonder, Berrenger, Brazen Brigade, Heart-Catchers, House of Rods and chains, and Caduceus (basically half of Eleutheria, aptly)

[spoiler]

Eleutheria is once ruled by two stars,  collectively known as "The Binary". The Binary is the Judgement that is responsible for the law of measurement and distance. The House of Rods and Chains along with its Master (Pennies, Menagerie, Pipe, Barleycorn, and 3 others?) are the servant of it. As usual for a Judgement back then, they were also served by Devils.

A collective of its Devil -led by an individual known as the Piper- and some lesser Judgements decide to rebel against the Great Chain of Beings and join(or create?) The Solonacean Conjuction, a proto-Revolutionaries. They seek the help of a fingerking who was known as a Storyteller. They decide to enlist The Binary into the Conjunction. Unexpectedly, one halved of the Binary, "The King Who Speaks", are interested in the Liberation. The Conjunction are invited to speak their cause to The Binary.

However the other halved of the Binary, "The King Who Wars", disagree with the Conjunction. He decide to uphold the Great Chain and maintain the status quo. Despite the plea of its other half, the Conjunction are banished from their hall.

Rejected, the Devils and the storyteller leave the hall. However TKWS follow them alone and said that he want to join the Conjunction in its revolution. It's a little bit vague on what and how, but the Conjunction basically convince TKWS to gave them its "armour", "shield", "vestment", "sword" and have it pledge his service to the Conjunction. Then the Conjunction "stab" his "unprotected soul" with "knives" and "drink his light". His death serve as a proof that the Conjunction can kill a Judgement. So shall it be in the name of the Revolution.

Grieving from the death of its half, TKWW rain fire and, well basically the Conjunction didn't stand a chance. The Devils then fled to Parabola via Caduceus. The storyteller and the lesser Judgements however didn't manage to fled, and the vengeful TKWW imprison the lesser Judgements to "burn forever in (his) palace". He also cast the storyteller unto a well where it will never escape until it manage to tell its story.

Presumably this is the point where the messenger and its masters (except Mr. Barleycorn) rebelled. Whatever the time period of their rebellion are, the end result of this is the death of the messenger and the master separated across the High Wilderness.

In the middle of its rampage, somehow someone or something has manage to convince TKWW to join the Liberation. The light of TKWW dims, until it finally emits no light. The Binary is now Halved. The creature that tell its story then transform and become known as the Second Storyteller... or more commonly known as the first of the Heart-Catchers, the first of the plant that advises. Whether their transformation into the first Heart-Catcher is the Halved's doing or not is unknown.

Sometime after the Halved lost its light, it command Lord Langley to create a sanctuary from the remain of of a library that is heavily implied to be the Pergamon Masse, the library of the Scrive Spinsters. Either the library or the Halved itself created the correspondence in Lord Langley's body that attract people to Langley Hall.

The Halved and Mr. Barleycorn also contact several Zee-Captain who delve into the Eye beneath the Zee with Zubmarine. It produces eyes in the body of those who pledge to be the messenger for the Liberation, which will open once someone enter Eleutheria. One of these Zee-captain is the Unassailable Founder, the captain of an experimental London Dreadnought The Berrenger. She stole the Berrenger from the admiralty and convince its crew to join the Liberation. She came to the Halved to pledge her allegiance, but for unknown reason the Halved denied her.
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