Rebecca Yarros has already teased a major next Empyrean Series book will take at least one other character's life, with Yarros suggesting it could be a fan-favorite.

Given Violet and Xaden's importance to the story, it's safe to assume both of them will make it to the fifth and final Empyrean novel — even if they face obstacles on the way there. And there's one Fourth Wing character we know is safe, as the epigraphs reveal that she's transcribing what happens over the course of the story: Jesinia. Everyone else's fate is up in the air. However, there are some characters who seem less likely to die in Onyx Storm's sequel, whether it's because their stories are just beginning or because they already had a close call with death.

8 Mira Sorrengail

Violet's Sister Already Comes Close To Death In Onyx Storm

With any luck, Lilith will be the last Sorrengail to die in the fight against the venin — but if another member of Violet's family perishes, I'm doubtful it will be Mira. After all, Mira has a close encounter with death at the Onyx Storm's silver-haired villain slashes Mira's throat. It's only thanks to a t effort between Brennan, Sloane, and Dain that Mira survives the confrontation.

With Mira having a death fakeout in Onyx Storm, it seems unlikely that Yarros would then proceed to kill her off in book 4. There would be little point to saving her in the first place, and using her against Violet again would feel like overkill. If anything, Brennan seems like the sibling who could be in danger in the sequel. But given the tensions between the Sorrengail siblings at the end of Onyx Storm — and the questions they still need to answer about their family — I'm hopeful all three of them will survive until at least book 5.

7 Ridoc Gamlyn

Ridoc's Luck May Keep Him Alive In Book 4

Ridoc is another character who has a few close calls with death in Onyx Storm, and he somehow walks away from all of them. Because of this, the theory that receives gifts on Zehyllna, he even gets a kiss on the cheek, while the other characters get more perplexing and hostile presents. Needless to say, Zihnal seems to be looking out for Ridoc, and that could help him make it through book 4.

I'm convinced he'll play a bigger and longer-lasting role — perhaps one connected to Zihnal.

Ridoc's signet is also evolving in interesting ways throughout Onyx Storm, so it'd be a shame to kill him before readers could see the full extent of that. And although getting rid of the comic relief would be a good way to up The Empyrean Series' stakes, it would also force a tonal shift that might make the next Fourth Wing book a little too dark. Ridoc's Onyx Storm story certainly cements him as a fan-favorite, so it's possible he's the death Yarros is referring to. However, I'm convinced he'll play a bigger and longer-lasting role — perhaps one connected to Zihnal.

6 Garrick Tavis

His Death Fakeout & Potential Romance Make It Unlikely

Garrick is yet another character who comes close to dying in Onyx Storm, as he's poisoned when Violet's Quest Squad visits Hedontis. Like Mira, he has a death fakeout that leaves readers and the other characters on edge prior to the fourth Empyrean Series book. Therefore, I feel like Yarros probably won't go after Garrick again so soon. I especially believe he's safe if Bodhi is the one who turns out to be Xaden's new venin brother. That makes Bodhi far more likely to die if Xaden were to lose a loved one in book 4.

Additionally, The Empyrean Series has yet to deliver on Imogen's and Garrick's potential romance, despite setting the stage for it throughout the first three books. It would be a shame to have them get together in the next Fourth Wing sequel, just to kill one of them not long after. Therefore, I think Garrick has a good chance of making it to the final installment. Whether he survives the entirety of the series is another story.

5 Sawyer Henrick

Sawyer Is Just Getting Back To The Action After Iron Flame

Sawyer has one of the most compelling arcs in Onyx Storm, as he learns to navigate walking and riding again after losing his leg in Iron Flame. His narrative is touching, but because it takes so long for him to come to with his new disability — and to recover physically — he's only just getting back to the action when Onyx Storm closes. It would be underwhelming to have Sawyer go through all that just to lose him so quickly in the next Empyrean Series book. It would also be too tragic a fate for him after everything he has overcome.

I think Sawyer's feelings for Jesinia give him a real shot at surviving.

Additionally, I think Sawyer's feelings for Jesinia give him a real shot at surviving, as we know the scribe makes it through the events of The Empyrean Series alive. I'm holding out hope that these two will get a happy ending when the final sequel is over and done with. It's unclear if Violet and Xaden will walk away from the war against the venin, but surely, at least one of Yarros' couples has to. It could be Sawyer and Jesinia.

4 Sloane Mairi

Her Siphoning Power Is Too Important To Lose

Sloane Mairi has a larger role in Onyx Storm than she does in Iron Flame, and Liam's sister also has one of the most fascinating signets in The Empyrean Series: siphoning. Sloane uses her power for important developments in both Iron Flame and Onyx Storm, and it feels like the story is setting up an even bigger use for it. Some theories even suggest that Sloane's siphoning signet could be used to cure riders who turn venin, which would make Sloane invaluable — and probably give her enough plot armor to make it through the next Fourth Wing sequel.

Killing Sloane after Fourth Wing already killed Liam would also be far too ruthless, even by The Empyrean Series' standards. It would be too tragic for the entire Mairi family to perish over the course of the story, and it would also be devastating if Violet couldn't keep her promise to Liam. I think it's more likely that Violet will follow through on it. And she may be glad that she did, as Sloane could be the answer to her biggest problems in Onyx Storm's sequel.

3 Andarna

Andarna Is Just Finding Herself & Tairn Is More Likely To Die

Andarna's Onyx Storm story is incredibly satisfying, as she embarks on a coming-of-age journey that allows her to become a more fully realized character. The search for Fourth Wing's seventh breed of dragon forces Andarna to contend with her place in the world, and she even temporarily leaves Violet to learn about her kind. She does return at the end of Onyx Storm, but there's no way that the book takes Andarna on this journey of self-discovery just to kill her in the next installment.

That's not to mention that Andarna has yet to realize her full potential on the battlefield, and more worried about Tairn perishing in Onyx Storm's sequel. He fits the mentor archetype, making him the more likely candidate, and Onyx Storm proves Violet can survive with just one bonded dragon.

2 Catriona Cordella

The Empyrean Series Hints At A Leadership Role For Her, Not Death

Although Xaden's ex, Catriona, is pretty unlikable throughout Iron Flame, she makes a better impression in Onyx Storm — and the series is clearly setting her up for big things in the future. Cat is initially interested in Xaden because she wants the title he can give her, but The Empyrean Series keeps hinting that she'll become a leader in a different way. The gift she receives on Zehyllna points to this, as the ruby necklace is reminiscent of the Duchess of Morraine, suggesting a connection of some sort. It could simply be that Cat will take on a similar role.

I believe Cat will eventually come to rule Poromiel though, and that makes me confident she'll survive the next Fourth Wing book.

When Violet and her friends return from their quest in Onyx Storm, Colonel Aetos also reveals that Cat is one step closer to the throne of Poromiel. Queen Maraya's death pushes her up in the line of succession, though Tecarus is currently the king. I believe Cat will eventually come to rule Poromiel though, and that makes me confident she'll survive the next Fourth Wing book — and perhaps the series overall.

1 Aaric/Cam Tauri

His Precog Signet & Title Will Likely Keep Him Around

Aaric is another character introduced in Iron Flame who's shaping up to be a much bigger player after Onyx Storm. Being King Tauri's son, Aaric's role in The Empyrean Series is going to be significant, no matter what happens to him. But after Halden's introduction and Navarre's consistently poor decision-making, it seems inevitable that Aaric will be tasked with paving a better future for the kingdom. I think King Tauri and Halden are likely to die in the coming books, which makes me all the more confident that Aaric will survive them.

Whether Aaric becomes king himself or puts a better governing system in place, he needs to make it to the final Empyrean Series novel. Like Sloane, Aaric also has a signet that's far too powerful and important to get rid of so soon after revealing it. His precognition power will probably be important in the next two sequels, and it could even be the key to finding Xaden. Needless to say, after seeing more of Aaric in Onyx Storm, I fully believe he'll at least make it to book 5.