Thunderclasts are the spren of ancient chasmfiends and other greatshells (spoilers through RoW)

[+Mzuka he/him]

So I'm not sure if this is a theory that's already out there and I'm late to the party - it's probably something a lot of people have speculated about, but I came across this quote in a WOBs Shardcast recently and decided to gather all of the evidence in one place:

Quote

ncmagic97

In Oathbringer, before the Battle of Thaylen City, Venli is able to see some of the Cognitive Shadows of the Fused waiting in the Cognitive Realm and mentions some are as large as buildings. Are thunderclasts actually a type of the Fused?

Brandon Sanderson

She doesn't know. Thunderclasts are something different, and that is what she is seeing. She is not correctly identifying them. Good question.

 

The panelists and questioner didn't remmeber the scene clearly (it's a confusing one), as Venli actually notes that the spren of the thunderclasts do not seem like regular Fused:

Quote

"Venli got to watch the thunderclasts awaken. Among the waiting spirits were two larger masses of energy—souls so warped, so mangled, they didn’t seem singer at all."

Sanderson, Brandon. Oathbringer: The Stormlight Archive Book Three . Orion. Kindle Edition. 

 

From WoK days, there have always been some parallels between thunderclasts and Fused: we see thunderclasts in the prologue, and then the Alethi assume that the chasmfiends are the Parshendi gods. Pre-Oathbringer, a lot of fans thought chasmfiends might actually be thunderclasts, though this was debunked.

There are, however, some further parallels between the two: the thunderclasts clearly have a degree of intelligence, as seen in the Battle of Thaylen City when one of them targets the King's Drop (receiving instructions from Odium via a Fused). The same creature is smart enough in its clash with Adolin to concentrate on him, identifying his Shardblade as the greatest threat to it: 

Quote

"For all the troops’ calls to distract the thing, however, it obviously knew who to focus on."

Sanderson, Brandon. Oathbringer: The Stormlight Archive Book Three . Orion. Kindle Edition. 

"Tell Yushah I want her to stay out here and guard the prison. Kai-garnis did well destroying the wall..." (Odium to a Fused)

Sanderson, Brandon. Oathbringer: The Stormlight Archive Book Three . Orion. Kindle Edition. 

 

In WoR, we get Kaladin and Shallan's perspective as they face a chasmfiend. The creature is cunning enough to wait for them, rather than going away once they hide in the slit in the wall. Kaladin observes:

Quote

"That face was like something from a nightmare. Evil, powerful, almost intelligent."

Sanderson, Brandon. Words of Radiance: 3 (The Stormlight Archive) . Orion. Kindle Edition. 

 

We also have one more instance - that I could find - of a character picking up on similarities between the two - this time when Adolin faces the chasmfiend:

Quote

"The beast regarded him with eyespots like molten rock just beneath the surface. He’d heard the descriptions of these things from his father’s visions—but looking up at it, he was struck by the shape of its face and head. A chasmfiend, he thought. It looks like a chasmfiend. The head, at least. The body was vaguely like a thick human skeleton."

Sanderson, Brandon. Oathbringer: The Stormlight Archive Book Three . Orion. Kindle Edition. 

We get a description of this head from Venli at the end of RoW:

Quote

"A shadow fell over Venli, and she started, staring up at a powerful long neck with a wicked arrowhead face on the end. A chasmfiend. Here. And no one was panicking. Storms. “That’s …” she whispered. “That’s how you got out of the chasms that night, during the storm?”"

Sanderson, Brandon. Rhythm of War (STORMLIGHT ARCHIVE) . Orion. Kindle Edition. 

The arrowface reminds me of the shape of the mandras who inhabit chasmfiends and other greatshells, enabling them to defy gravity. As for why the spren of ancient chasmfiends - and possibly other greatshells - would be assisting the souls of ancient singers in an eternal war against the humans, the scene quoted above may hold the answer. At the end of RoW, Venli finds the remaining listeners and discovers that they have somehow bonded or befriended the chasmfiends, who helped them survive the chasms.

As we are often told, new things are made from old things. It seems plausible that the ancient singers may have had this ability, as this kind of symbiosis is common for Rosharan species. For singers, this bond may grant them protection, while for chasmfiends - and greatshells in general - it might increase their intelligence/cognition, similar to the Nahel bond: new things are made from old things.

We have seen in Rhythm of War that Chiri-Chiri - a larkin -  has developed her intelligence to the point that she can speak with "mouth noises". If the ancient singers had this bond with chasmfiends and other greatshells back at the time of the First Desolation, and it did indeed enhance their intelligence, then I think Odium may have Elevated these greatshells into what we now see as thunderclasts. When they manifest, they rip free of the earth, forming a great shell of stone around their spirit.

Edited September 2, 2022 by Mzuka
SPOILER TAG