Sustaining a fantasy series is one of the most difficult tasks every genre writer faces. While some authors begin writing their series with a clear idea of where the story and character arcs are going, this isn't always the case. Though this doesn't necessarily mean that the following installments will be weaker than book one, it can cause some issues in the overall cohesion of the work. The sequels in this fantasy series aren't bad or low quality, but the first novel starts on such a high note that the rest of the installments end up being a little disappointing.

Like the fantasy TV shows that fell off after season 1, these book series fall victim to classic pitfalls within the fantasy genre. Whether this means the character development stalls out, the themes become repetitive, or the tone takes a sharp turn that leaves the audience confused, there are many ways for fantasy novels to veer off course. Additionally, since the strong first installment has so many great moments and compelling story beats, it sets a high bar that the author can't live up to with every new iteration of the series.

5 Gentleman Bastard Sequence (2006–Present)

Written by Scott Lynch

The Lies of Locke Lamora, the first book in the Gentleman Bastard Sequence, is a recent fantasy book that will be a classic one day. However, after Scott Lynch penned the first installment of the series, Locke's adventures began to lose their edge. Getting to know Locke, the protagonist, and entering his world of thievery and deceit was one of the best parts of The Lies of Locke Lamora. While he's a strong enough character that readers would follow him anywhere, the other books don't use him as effectively.

Lynch is still in the process of completing the fourth book in the series, The Thorn of Emberlain, and has released a few novellas and stories to keep readers happy in the meantime. However, even though many of us will continue reading Lynch's next installment and keep up with Locke's misadventures, Lynch should return to the elements that made the first book so strong. Using urban fantasy themes and introducing some new tricks we haven't seen Locke pull will help put the Gentleman Bastards Sequence back on the right course.

4 Lightbringer (2010–2019)

Written by Brent Weeks

The magic system in Brent Weeks' Lightbringer series immediately grabs the audience's attention. Using scientific principles of light and color and infusing them with otherworldly magic is a unique way to craft a fantastical world. Additionally, The Black Prism, book one of the series, includes a plot twist that will knock the reader's socks off. Not only is it shocking, but it changes the way the novel is read, making you want to go back and reread from the beginning.

Unfortunately, when there's a twist this good in the first book of a series, this makes it difficult to top the audience's surprise and delight in the remaining installments. Though it's still exciting to follow the characters on their journeys, and there are many secrets that must come to light, it's hard not to feel somewhat disappointed when the other books don't live up to The Black Prism. To compensate, Weeks adds new rivals and antagonists, but none are as strong as in The Black Prism.

3 The Demon Cycle

Written by Peter V. Brett

Though Peter V. Brett's The Demon Cycle includes five primary works and several one-off novellas, The Painted Man, also known as The Warded Man, is the installment that will captivate readers. There are still some deeply questionable themes and messages in The Painted Man that Brett doesn't address, but the world-building and story are at their best in book one. However, the elements that could've propelled the narrative forward into the following novels start to fade, and the characters become more like archetypes instead of fully fleshed-out individuals.

Unfortunately, the issues in The Demon Cycle that could've been solved with the following books only got worse as the series progressed.

Unfortunately, the issues in The Demon Cycle that could've been solved with the following books only got worse as the series progressed. The treatment of female characters is a huge problem in all the works, and Brett didn't improve upon this in the later works. In some ways, the real point of contention of the remaining books in The Demon Cycle is that the secondary characters and larger world all fall flat when compared to the antagonist and protagonist, who take up most of the pages, making the world as a whole less compelling.

2 Winterlands (1985–2002)

Written by Barbara Hambly

Barbara Hambly's Winterlands series s the ranks of some of the best books about dragons, and Dragonsbane is easily the best work in Hambly's fantasy universe. In Dragonsbane, Gareth, John Aversin, and Jenny Waynest make a formidable trio, even in the face of the world's most powerful dragons. However, their character development and dynamics are at their best in the first book. After Dragonsbane, Aversin and Waynest's journeys become repetitive, and it's clear that Hambly's vision for the series was beginning to fade after book one.

There are many sequel, but the Winterlands series is a standout. Though Dragonsbane is the most enticing of the series, and the books don't have quite as much romance as the Empyrean Series, they share a love for dragons and an interest in this facet of fantasy. It isn't difficult to find fictional worlds that use dragons as terrifying beasts that must be defeated, but Dragonsbane set itself apart. Diving into the first book is definitely worth it, even if the sequels aren't as attention-grabbing.

1 The Founders Trilogy (2018–2022)

Written by Robert Jackson Bennett

Diving headfirst in Robert Jackson Bennett's The Founders Trilogy is easy in Foundryside, the first book in the series. Sancia Grado makes a sharp and compelling protagonist, and Bennett sets the bar for himself very high with the crafty heist and subtle romance at the heart of Foundryside​​​​​​. What makes Foundryside compulsively readable is the way Bennett sets it apart from typical genre conventions, using the tropes of the heist and the dangerous fantasy world as the beginning of his overarching themes and character development.

Though Bennett's writing is no less well-crafted, the way the stakes are raised in each book results in intense changes in the style and tone of the work.

Shorefall and Locklands, Benett's follow-ups to the spellbinding Foundryside, are still strong fantasy books and enjoyable reads. However, Foundryside told a tight, complete story that didn't really require sequels. Bennett didn't leave enough up in the air, typing up so many of his loose ends that the next two installments felt like Bennett was dragging out a narrative that had already been told. Though Bennett's writing is no less well-crafted, the way the stakes are raised in each book results in intense changes in the style and tone of the work.