Sebastien de Castell
@decastell.bsky.social
I write swashbuckling fantasy novels such as Traitor’s Blade, Spellslinger, Play of Shadows and Malevolent Seven. My books have been translated into fifteen languages and are available in ebook, hardback, paperback and audiobook.
What's the biggest misconception about being a professional author? 🤔
As William Goldman said, “Nobody knows anything.” That's the publishing world for you—full of unpredictability! One day it’s success, the next, who knows? But I love every moment!
#AuthorLife #WritingCommunity
As William Goldman said, “Nobody knows anything.” That's the publishing world for you—full of unpredictability! One day it’s success, the next, who knows? But I love every moment!
#AuthorLife #WritingCommunity
February 6, 2026 at 9:50 PM
What's the biggest misconception about being a professional author? 🤔
As William Goldman said, “Nobody knows anything.” That's the publishing world for you—full of unpredictability! One day it’s success, the next, who knows? But I love every moment!
#AuthorLife #WritingCommunity
As William Goldman said, “Nobody knows anything.” That's the publishing world for you—full of unpredictability! One day it’s success, the next, who knows? But I love every moment!
#AuthorLife #WritingCommunity
Our Lady of Blades is coming.
Not everything will be shared publicly.
Early reveals, limited editions, and quiet details go to the newsletter first—before the wider world catches on.
decastell.com/secrets/
#OurLadyOfBlades #ComingSoon
Not everything will be shared publicly.
Early reveals, limited editions, and quiet details go to the newsletter first—before the wider world catches on.
decastell.com/secrets/
#OurLadyOfBlades #ComingSoon
February 5, 2026 at 2:02 PM
Our Lady of Blades is coming.
Not everything will be shared publicly.
Early reveals, limited editions, and quiet details go to the newsletter first—before the wider world catches on.
decastell.com/secrets/
#OurLadyOfBlades #ComingSoon
Not everything will be shared publicly.
Early reveals, limited editions, and quiet details go to the newsletter first—before the wider world catches on.
decastell.com/secrets/
#OurLadyOfBlades #ComingSoon
Did you know? 🏰 Castel Sant’Angelo in Rome is linked to the Vatican by an 800m secret tunnel, the Passetto di Borgo, used by Popes to escape during invasions! 🕵️♂️
#HistoricCastles #CastleFacts #HistoryNerd
#HistoricCastles #CastleFacts #HistoryNerd
February 4, 2026 at 6:00 PM
Did you know? 🏰 Castel Sant’Angelo in Rome is linked to the Vatican by an 800m secret tunnel, the Passetto di Borgo, used by Popes to escape during invasions! 🕵️♂️
#HistoricCastles #CastleFacts #HistoryNerd
#HistoricCastles #CastleFacts #HistoryNerd
Join me today at 11 am ET for a LIVE chat on Technology Revolution: The Future of Now, with Bonnie D. Graham
Talking on The Future of Authors + AI: Anything But Writing
Join us LIVE:
www.youtube.com/@BonnieDRadi...
#interview #bookchat
Talking on The Future of Authors + AI: Anything But Writing
Join us LIVE:
www.youtube.com/@BonnieDRadi...
#interview #bookchat
February 4, 2026 at 1:22 PM
Join me today at 11 am ET for a LIVE chat on Technology Revolution: The Future of Now, with Bonnie D. Graham
Talking on The Future of Authors + AI: Anything But Writing
Join us LIVE:
www.youtube.com/@BonnieDRadi...
#interview #bookchat
Talking on The Future of Authors + AI: Anything But Writing
Join us LIVE:
www.youtube.com/@BonnieDRadi...
#interview #bookchat
In my chat with Bookish Whimsy, I discussed how fencing shapes my action and dialogue writing. A duel has its own rhythm, much like conversations. When done right, readers truly feel the scene.
bookishwhimsy.blogspot.com/2014/07/inte...
#BookChat #WritingTips #Fencing
bookishwhimsy.blogspot.com/2014/07/inte...
#BookChat #WritingTips #Fencing
February 3, 2026 at 2:50 PM
In my chat with Bookish Whimsy, I discussed how fencing shapes my action and dialogue writing. A duel has its own rhythm, much like conversations. When done right, readers truly feel the scene.
bookishwhimsy.blogspot.com/2014/07/inte...
#BookChat #WritingTips #Fencing
bookishwhimsy.blogspot.com/2014/07/inte...
#BookChat #WritingTips #Fencing
Huge thanks to everyone who came out for Swords, Fights, and Spellslingers with the dangerously talented Miles Cameron. Stories were swapped, fantasy was debated, and no one escaped entirely unscathed (emotionally).
Always a pleasure meeting readers.
Always a pleasure meeting readers.
February 2, 2026 at 5:48 PM
Huge thanks to everyone who came out for Swords, Fights, and Spellslingers with the dangerously talented Miles Cameron. Stories were swapped, fantasy was debated, and no one escaped entirely unscathed (emotionally).
Always a pleasure meeting readers.
Always a pleasure meeting readers.
How do you stay motivated while writing?
For me, it’s about honoring the readers who support my work and finding a meaningful theme that drives the story. ✍️📚
#fridayvibe #writing #motivation
For me, it’s about honoring the readers who support my work and finding a meaningful theme that drives the story. ✍️📚
#fridayvibe #writing #motivation
January 30, 2026 at 4:09 PM
How do you stay motivated while writing?
For me, it’s about honoring the readers who support my work and finding a meaningful theme that drives the story. ✍️📚
#fridayvibe #writing #motivation
For me, it’s about honoring the readers who support my work and finding a meaningful theme that drives the story. ✍️📚
#fridayvibe #writing #motivation
In a few hours, the swords come out.
I’ll be at Indigo Bay & Bloor with Miles Cameron for Swords, Fights, and Spellslingers—signing books, handing out swag, and talking fantasy until someone makes us stop.
🕞 3:30–6 PM
📍 Indigo Bay & Bloor, Toronto
I’ll be at Indigo Bay & Bloor with Miles Cameron for Swords, Fights, and Spellslingers—signing books, handing out swag, and talking fantasy until someone makes us stop.
🕞 3:30–6 PM
📍 Indigo Bay & Bloor, Toronto
January 30, 2026 at 4:00 PM
In a few hours, the swords come out.
I’ll be at Indigo Bay & Bloor with Miles Cameron for Swords, Fights, and Spellslingers—signing books, handing out swag, and talking fantasy until someone makes us stop.
🕞 3:30–6 PM
📍 Indigo Bay & Bloor, Toronto
I’ll be at Indigo Bay & Bloor with Miles Cameron for Swords, Fights, and Spellslingers—signing books, handing out swag, and talking fantasy until someone makes us stop.
🕞 3:30–6 PM
📍 Indigo Bay & Bloor, Toronto
Tomorrow, swords will be crossed and books signed! Join me and the talented Miles Cameron for Swords, Fights, and Spellslingers.
📍 Indigo Bay & Bloor, Toronto
🕞 3:30–6:00 PM
✨ Free swag. Signed books. Questionable wisdom.
Come say hello or challenge us! Your move.
📍 Indigo Bay & Bloor, Toronto
🕞 3:30–6:00 PM
✨ Free swag. Signed books. Questionable wisdom.
Come say hello or challenge us! Your move.
January 29, 2026 at 11:00 PM
Tomorrow, swords will be crossed and books signed! Join me and the talented Miles Cameron for Swords, Fights, and Spellslingers.
📍 Indigo Bay & Bloor, Toronto
🕞 3:30–6:00 PM
✨ Free swag. Signed books. Questionable wisdom.
Come say hello or challenge us! Your move.
📍 Indigo Bay & Bloor, Toronto
🕞 3:30–6:00 PM
✨ Free swag. Signed books. Questionable wisdom.
Come say hello or challenge us! Your move.
“There’s a trick to fighting on the deck of a ship. I don’t know what it is, but I fully intend to find out one day.”
~Falcio
decastell.com/book/tyrants...
#humour #humor #fantasy #bookquote #bookchat
~Falcio
decastell.com/book/tyrants...
#humour #humor #fantasy #bookquote #bookchat
January 29, 2026 at 2:36 PM
“There’s a trick to fighting on the deck of a ship. I don’t know what it is, but I fully intend to find out one day.”
~Falcio
decastell.com/book/tyrants...
#humour #humor #fantasy #bookquote #bookchat
~Falcio
decastell.com/book/tyrants...
#humour #humor #fantasy #bookquote #bookchat
Fun Castle Fact: Château de Chenonceau! 🏰✨ Its gallery served as an escape route during WWII—one side Nazi-occupied, the other "Free France."
Location: Loire Valley, France
Year Started: 1514
Size: Built over the River Cher.
#HistoryNerd #CastleFact #CastleLovers #DidYouKnow
Location: Loire Valley, France
Year Started: 1514
Size: Built over the River Cher.
#HistoryNerd #CastleFact #CastleLovers #DidYouKnow
January 28, 2026 at 1:12 PM
Fun Castle Fact: Château de Chenonceau! 🏰✨ Its gallery served as an escape route during WWII—one side Nazi-occupied, the other "Free France."
Location: Loire Valley, France
Year Started: 1514
Size: Built over the River Cher.
#HistoryNerd #CastleFact #CastleLovers #DidYouKnow
Location: Loire Valley, France
Year Started: 1514
Size: Built over the River Cher.
#HistoryNerd #CastleFact #CastleLovers #DidYouKnow
Modern Romantic Podcast: Finding Beauty
I had such a great time talking on the Modern Romantic Podcast.
Check it out: www.youtube.com/watch
#bookchat #interview #FantasyReaders
I had such a great time talking on the Modern Romantic Podcast.
Check it out: www.youtube.com/watch
#bookchat #interview #FantasyReaders
January 27, 2026 at 5:23 PM
Modern Romantic Podcast: Finding Beauty
I had such a great time talking on the Modern Romantic Podcast.
Check it out: www.youtube.com/watch
#bookchat #interview #FantasyReaders
I had such a great time talking on the Modern Romantic Podcast.
Check it out: www.youtube.com/watch
#bookchat #interview #FantasyReaders
Back in Toronto for book promo—catching up with my brother & writer friends. Fun facts: Merril Collection (massive SFF archive), the PATH (largest underground walkway), Spawn was created here, and Ad Astra supports Canadian fantasy writers.
#Toronto #BookPromo #FantasyFans
#Toronto #BookPromo #FantasyFans
January 27, 2026 at 4:30 PM
Back in Toronto for book promo—catching up with my brother & writer friends. Fun facts: Merril Collection (massive SFF archive), the PATH (largest underground walkway), Spawn was created here, and Ad Astra supports Canadian fantasy writers.
#Toronto #BookPromo #FantasyFans
#Toronto #BookPromo #FantasyFans
Back in Toronto for book promo! Catching up with my brother & writer friends. Fun facts: Merril Collection (huge SFF archive), the PATH (world’s largest underground walkway), Spawn was created here, and Ad Astra champions Canadian fantasy.
#Toronto #BookPromo #FantasyFans
#Toronto #BookPromo #FantasyFans
January 26, 2026 at 4:29 PM
Back in Toronto for book promo! Catching up with my brother & writer friends. Fun facts: Merril Collection (huge SFF archive), the PATH (world’s largest underground walkway), Spawn was created here, and Ad Astra champions Canadian fantasy.
#Toronto #BookPromo #FantasyFans
#Toronto #BookPromo #FantasyFans
Is there an author whose writing makes you envious?
Miles Cameron writes daily, driven by curiosity and narrative mischief. That's a real writer!
#FridayVibes #QuestionOfTheDay
Miles Cameron writes daily, driven by curiosity and narrative mischief. That's a real writer!
#FridayVibes #QuestionOfTheDay
January 23, 2026 at 3:42 PM
Is there an author whose writing makes you envious?
Miles Cameron writes daily, driven by curiosity and narrative mischief. That's a real writer!
#FridayVibes #QuestionOfTheDay
Miles Cameron writes daily, driven by curiosity and narrative mischief. That's a real writer!
#FridayVibes #QuestionOfTheDay
"It’s much too cold and wet here for a king to bother coming all the way out here to rule."
~ Brother Agneta
decastell.com/book/crucibl...
#bookcharacters #author #crucibleofchaos
~ Brother Agneta
decastell.com/book/crucibl...
#bookcharacters #author #crucibleofchaos
January 22, 2026 at 10:12 PM
"It’s much too cold and wet here for a king to bother coming all the way out here to rule."
~ Brother Agneta
decastell.com/book/crucibl...
#bookcharacters #author #crucibleofchaos
~ Brother Agneta
decastell.com/book/crucibl...
#bookcharacters #author #crucibleofchaos
Fun Castle Fact
Built in 1514, Hampton Court Palace wasn’t just a royal home—it was a food factory.
Henry VIII’s kitchens made 800 meals a day, and the court drank 600,000 gallons of beer a year.
Power, apparently, came by the barrel. 🍺⚔️
#FunCastleFacts #HistoryNerd #Worldbuilding #FantasyAuthor
Built in 1514, Hampton Court Palace wasn’t just a royal home—it was a food factory.
Henry VIII’s kitchens made 800 meals a day, and the court drank 600,000 gallons of beer a year.
Power, apparently, came by the barrel. 🍺⚔️
#FunCastleFacts #HistoryNerd #Worldbuilding #FantasyAuthor
January 21, 2026 at 2:25 PM
Fun Castle Fact
Built in 1514, Hampton Court Palace wasn’t just a royal home—it was a food factory.
Henry VIII’s kitchens made 800 meals a day, and the court drank 600,000 gallons of beer a year.
Power, apparently, came by the barrel. 🍺⚔️
#FunCastleFacts #HistoryNerd #Worldbuilding #FantasyAuthor
Built in 1514, Hampton Court Palace wasn’t just a royal home—it was a food factory.
Henry VIII’s kitchens made 800 meals a day, and the court drank 600,000 gallons of beer a year.
Power, apparently, came by the barrel. 🍺⚔️
#FunCastleFacts #HistoryNerd #Worldbuilding #FantasyAuthor
I had such a fun time with @thefantasyhive.bsky.social talking about "The Fantastical Magic of the Ordinary World."
fantasy-hive.co.uk/.../the-fant...
#playofshadows #bookchat #fantasybooks
fantasy-hive.co.uk/.../the-fant...
#playofshadows #bookchat #fantasybooks
The Fantastical Magic of the Ordinary World - GUEST POST by Sebastien de Castell (PLAY OF SHADOWS) | Fantasy-Hive
To celebrate the release of his first book in a brand new series, PLAY OF SHADOWS, Sebastien de Castell joins us and explores the process behind creating magic systems
fantasy-hive.co.uk
January 20, 2026 at 6:16 PM
I had such a fun time with @thefantasyhive.bsky.social talking about "The Fantastical Magic of the Ordinary World."
fantasy-hive.co.uk/.../the-fant...
#playofshadows #bookchat #fantasybooks
fantasy-hive.co.uk/.../the-fant...
#playofshadows #bookchat #fantasybooks
Just when I thought I couldn't take on more book requests, I found a gem by Jake Brrr❄️. A wild fantasy ride filled with mystery and underdogs racing against time! Can’t wait to dive in! 📚✨ #MondayMotivation #AuthorLife #ComingSoon #FantasyBooks
January 20, 2026 at 4:09 PM
Just when I thought I couldn't take on more book requests, I found a gem by Jake Brrr❄️. A wild fantasy ride filled with mystery and underdogs racing against time! Can’t wait to dive in! 📚✨ #MondayMotivation #AuthorLife #ComingSoon #FantasyBooks
I often get asked for tips on writing fight scenes. Here are two key techniques:
1. Let readers choreograph the fight.
2. Build tension and stakes beyond the action.
For more, check out: decastell.com/2014/07/23/5...
#WritingTips #FightScenes #CreativeWriting 💥📚
1. Let readers choreograph the fight.
2. Build tension and stakes beyond the action.
For more, check out: decastell.com/2014/07/23/5...
#WritingTips #FightScenes #CreativeWriting 💥📚
January 16, 2026 at 1:56 PM
I often get asked for tips on writing fight scenes. Here are two key techniques:
1. Let readers choreograph the fight.
2. Build tension and stakes beyond the action.
For more, check out: decastell.com/2014/07/23/5...
#WritingTips #FightScenes #CreativeWriting 💥📚
1. Let readers choreograph the fight.
2. Build tension and stakes beyond the action.
For more, check out: decastell.com/2014/07/23/5...
#WritingTips #FightScenes #CreativeWriting 💥📚
“It’s stories that inspire people to change. It’s stories that make them believe things can be better.”
~Falcio
decastell.com/book/knights...
#greatcoats #characterquotes #author #Fantasy
~Falcio
decastell.com/book/knights...
#greatcoats #characterquotes #author #Fantasy
January 15, 2026 at 5:53 PM
“It’s stories that inspire people to change. It’s stories that make them believe things can be better.”
~Falcio
decastell.com/book/knights...
#greatcoats #characterquotes #author #Fantasy
~Falcio
decastell.com/book/knights...
#greatcoats #characterquotes #author #Fantasy
Did you know? 🏰 Kronborg Castle in Helsingør, Denmark, built in 1574, features a 203-ft Banquet Hall. It inspired Shakespeare’s Hamlet and profited from taxing Baltic Sea ships! 💰 #CastleFact #HistoryFact #WritersLife #Author
January 14, 2026 at 5:36 PM
Did you know? 🏰 Kronborg Castle in Helsingør, Denmark, built in 1574, features a 203-ft Banquet Hall. It inspired Shakespeare’s Hamlet and profited from taxing Baltic Sea ships! 💰 #CastleFact #HistoryFact #WritersLife #Author
I always have a great time talking about Play of Shadows. Thank you so much Track of Words.
www.trackofwords.com/2024/03/28/a...
#author #interview #playofshadows
www.trackofwords.com/2024/03/28/a...
#author #interview #playofshadows
January 13, 2026 at 7:57 PM
I always have a great time talking about Play of Shadows. Thank you so much Track of Words.
www.trackofwords.com/2024/03/28/a...
#author #interview #playofshadows
www.trackofwords.com/2024/03/28/a...
#author #interview #playofshadows
Feeling grateful for my health! Had a wild ER visit in Cambodia for kidney stones, but no serious issues. Just wrapped up a check-up with a physio in Vancouver and I’m excited to improve my mobility and strength over the next two months! 🏋️♂️💪 #HealthJourney #Resilience #AdventureAwaits
January 12, 2026 at 6:01 PM
Feeling grateful for my health! Had a wild ER visit in Cambodia for kidney stones, but no serious issues. Just wrapped up a check-up with a physio in Vancouver and I’m excited to improve my mobility and strength over the next two months! 🏋️♂️💪 #HealthJourney #Resilience #AdventureAwaits
Do you have any writing bad habits?
My redoubtable editor, Jo Fletcher, used to say of the Greatcoats novels, “You can make Falcio as maudlin and introspective as you want in the first half of the book, but I’m cutting those bits from the last act.” Tens of thousands of readers thank you, Jo.
My redoubtable editor, Jo Fletcher, used to say of the Greatcoats novels, “You can make Falcio as maudlin and introspective as you want in the first half of the book, but I’m cutting those bits from the last act.” Tens of thousands of readers thank you, Jo.
January 9, 2026 at 5:23 PM
Do you have any writing bad habits?
My redoubtable editor, Jo Fletcher, used to say of the Greatcoats novels, “You can make Falcio as maudlin and introspective as you want in the first half of the book, but I’m cutting those bits from the last act.” Tens of thousands of readers thank you, Jo.
My redoubtable editor, Jo Fletcher, used to say of the Greatcoats novels, “You can make Falcio as maudlin and introspective as you want in the first half of the book, but I’m cutting those bits from the last act.” Tens of thousands of readers thank you, Jo.