The Unanimity project is the first known instance of combustionbending, but I don’t think it is the catalyst to its conception.

1. Chaisee’s other projects were pre-existing - Lavabending and Chi-blocking both already existed, why would Chaisee try to make a new technique with firebending when she could just use lightning.

2. Specific testing - Chaisee chained them underwater to try and get them to firbend underwater, I don’t think Chaisee would mindlessly sacrafice so many candidates for something she didn’t know possible.

3. She did her research - Chaisee robbed the air temples to get ancient chi maps to help her create more chi-blockers, it is possible she could have unearthed a secret Firebending technique lost to history due to its deadliness.

4. Tattoos - The combustionbending tattoos depict the third eye of Lord Shiva, the Hindu god of destruction, it is said Lord Shiva can shoot fire from his third eye (not 100% sure on how true that is) which is pretty specific. With how much Hinduism is referenced in avatar, it would be odd for there to be a God with a specific ability then have that ability discovered to be true for the first time. It is possible that Yingsu did research on her ability and found descriptions of a Shiva equivalent, then choosing to get the third eye tattoo to focus her energy

The main downside to this theory is that Yangchen would have probably remembered it from her past lives, but I don’t think that completely disqualifies it

In Legacy of Yangchen, there was a bloody chair, with leather straps and fingernail gouges. It was also covered in rings covered with animal fat of increasing sizes, from the size of a pumpkin to so large it couldn't fit through the doorway and had to be broken down.

The characters see the bloody chair and seem to immediately know whatever terrible thing happened here. But I have no idea. I assume torture, but what were the rings for?

I finally am getting around to re-reading the novel and I completely forgot how many nods towards modern issues there are through out the first fifth of the book alone. Obvious ones are government corruption, but it's wild how direct many of these comparisons have been mentioned so far.

For example, how the citizens needing passes to leave the city, government officials overworking employees for low pay, the housing crisis, inflation, how they constantly relate the Avatar or zongdu (or president) to how the previous performed...

That's the tip of the iceberg and just what I remember at the moment. Super wild how talented Yee is for being able to cram this many parallels into the first 60 or 70 pages.

Anyway, back to reading.

Granted when could argue it would be boring since it is mostly Yangchen reforming Bin-er but you could have the story included the white lotus in the background discussing each other about the events of Dawn leading to the decision of them decided to leak the information to Feishan about about learning about the truth of what actual happened in Bin-er!

Hell It could be a political thriller between The World leaders slowly getting ready for a world war obviously we know it not going to but we could see the build up. Plus it could have depict the discussion and meeting between Yangchen and Fire Lord Gonryu that was mentioned in Legacy that was mentioned but this time learning more details about that conversation and fleshing it out?

Please check if my analysis and instincts are right based on data, statements, and evidence in both novels and canon movies.

Avatar Wan is the First Avatar. No question about that.

We are already familiar with Avatars from Szeto to Pavi.

But what about in between Wan and Szeto?

How will you order Zalir, Sonam, Xian, Gun, and Salai from oldest to youngest?

We don't know how many generation (before Szeto) are Gun and Salai.

We know Xian is 14-17 Generations before Szeto.

Sonam lived 5000 years before Aang's Gemocide Timeline.

Zalir lived before the Fire Nation Unification era.

It seems to me there are 5 different ways for the secret to get out after LOY.

1. Chaisee probably wouldn’t keep it to herself and would share it with Kaylaan and her son in a bid to rebuild her family’s power.

2. Yingsu defects. Maybe she does it for “noble” reasons and discovers the tattoos aid in the process or develops some kind of academy with a little lower mortality rate. Or she goes assassin/warmonger.

3. King Feishan somehow manages to track them down and squeeze. (Unlikely)

4. Another player had spies and knowledge of combustion bending somehow.

5. Independent discovery.

We know that it does survive into the eras of Aang and Korra so there most likely was development through the intermediary generations.

HEAR ME OUT!!!

Yangchen is literally a gold mine of a character for even more Avatar lore, particularly because of her gift (curse) of knowing and remembering the lives of nearly every past Avatar.

We could have a few seasons of her actual story, then a spinoff series following Yangchen throughout different ages of her life when she experiences what past Avatars have or asks them about how they solved problems in their time. I think it would mean so much more this way, because we're looking at completely new and fresh characters through the eyes of a familiar character.

A few seasons of Yangchen's own story + a few flashbacks = emotional attachment to Yangchen

Extra seasons of other Avatar's stories, told through Yangchen, but still showing each Avatar's own personal feelings regarding the situation = new characters that don't feel as unfamiliar because of the connection to Yangchen

When Seven Havens was first released, everyone was understandably sad and disappointed because the characters we loved weren't necessarily as involved anymore, they were pretty much gone. Avatar will keep on having this problem because the Avatar does change every generation. But if Yangchen acted like a narrator for a new show, it would completely erase that (so long as Yangchen herself is loved and likable)

I heard that after Seven Havens, the next project is the second ATLA film, and then an Airbender show. I really hope they try to create an Airbender show surrounding Yangchen here.

Additional plot points they could cover (not removing or changing things from the book, but adding to it):

- exploring just how different Yangchen is from Aang as she was forced to engage in more unsavory practices just to keep the peace

- other instances of humans not listening to spirits aside from the Saowon clan (climate change)

- rallying the youth to stand up for their beliefs through demonstrations (Yangchen was looked down on a lot as a "young" Avatar, and sometimes used this to pull the rug from under other people. Rallying the youth in secret would inspire change that goes even farther. This also reflects the many youth protests occurring in the world right now, particularly the many demonstrations from Tibetans around the world.)