The sour taste left by the final few seasons of Game of Thrones still lingers in the mouths of many of the show's fans. For a series with so much potential, it really is both disappointing and perplexing just how amateurish the show's conclusion ended up being. In many ways though, the nosedive in quality was perhaps a little predictable.

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It's no coincidence that the decline in standards coincided with the show catching up with the as yet unfinished book series. Without fresh source material and a team who didn't seem to understand their own show, it never really stood a chance. What many people might not realize, however, is that the show had already been deviating from the books for quite some time at this point; with many of the books' important characters cut from the show entirely.

10 Strong Belwas

Belwas learned how to fight in the fighting pit of Meereen (Game of Thrones)

Belwas was sent to protect Daenerys by Ilyrio and first meets up with the Mother of Dragons in Quarth. He subsequently joins her Queensguard and later becomes a member of Meereen's ruling council as well. Having honed his combat skills in the fighting pits of Meereen, he's one of the fiercest warriors in the books and has never lost a fight. He's not the brightest bulb in the box though.

The latest book ends with Meereen surrounded by enemies and Belwas volunteering himself for the position of the city's champion. Whether or not he'll actually end up fighting remains to be seen. If he does though, his strong track record suggests that he'll probably emerge victorious.

9 Victarion Greyjoy

Victarion Greyjoy should have appeared at the Kingsmoot following the death of his brother, Balon (Game of Thrones)

Much like the Dornish folk, the portrayal of the Greyjoys in the show is incredibly underwhelming when compared to the books. As well as renaming Theon's sister from Asha to Yara and completely ruining his uncle Euron, the writers also decided to cut one of his other uncles out of the show entirely.

Victarion Greyjoy is a prominent character in the fourth and fifth books and will almost certainly be so again if or when The Winds of Winter finally releases. He's currently on his way to propose to Daenerys having also recently learned of a magical horn that will supposedly give him power over her dragons.

8 Lady Stoneheart

Catelyn Stark becomes Lady Stoneheart following the events of the red wedding (Game of Thrones)

While the red wedding brought about the untimely end of many of the Stark family and their banner men, there's one important character who came out of it alive. Well. Sort of. Although Catelyn does get her throat slit in the books, her lifeless corpse is later revived by Beric Dondarrion at the cost of his own life.

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Now going by the name of Lady Stoneheart and having lost her mind after witnessing the murder of her firstborn son, she returns as a completely different woman. She takes control of the Brotherhood and seeks only vengeance against those who she believes to have wronged the Stark family. The fifth book ends with her preparing to hang Brienne for supposedly breaking her sworn oath.

7 Marwyn the Mage

Marwyn the Mage is one of the most knowledgeable maesters at the Citadel (Game of Thrones)

The Order of Maesters is another group that's often neglected in the show. As well as there being no mention of Jaqen H'ghar's attempts to infiltrate the citadel, one of the order's most interesting members is completely absent from the show.

Marwyn the Mage is an archmaester of the citadel and one of the few members of the order who understands and believes in magic. He's incredibly well-traveled and is currently on his way to Meereen to meet with Daenerys. Given that it was Marwyn who taught Mirri Maz Duur about blood magic though, he might not be receiving too warm a welcome. Well. Either that, or he'll be treated to a welcome so warm that he'll be unrecognizable afterward.

6 Jeyne Westerling

Jeyne Westerling is currently under house arrest at Riverrun (Game of Thrones)

Jeyne Westerling isn't a particularly well-fleshed out character in the books, although she is a fairly significant one. She's the widow of Rob Stark, who in the show marries Talisa Maegyr instead. The latter is undoubtedly a far more interesting character, but Jeyne may yet prove to be more significant.

While, at first, it might seem like little more than a straight swap, there is one important difference between the two characters. Jeyne didn't attend the Red Wedding and is therefore still alive in the books. She doesn't appear to be pregnant with Rob's child and is currently under house arrest at Riverrun, but - unlike Talisa - she could still have a part to play as events continue to unfold.

5 Patchface

Patchface grew up on the island of Dragonstone (Game of Thrones)

Although not mentioned in the show, Robert, Renly, and Stannis were orphaned at a young age after a shipwreck claimed the lives of their parents as well as hundreds of Baratheon men. The sole survivor from this tragedy was Patchface, who washed ashore three days later having lost both his memory and his mind.

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The young jester becomes very close with Shireen (who, for the moment, at least, is still alive in the books) and even accompanies Stannis to Castle Black. It's here that Melisandre tells Jon Snow that she's seen visions of Patchface in the flames and believes him to be incredibly dangerous. Despite this, readers are still to be given any clear indication that he actually is.

4 Young Griff

Young Griff was supposedly smuggled out of King's Landing before the mountain murdered his mother and sister (Game of Thrones)

It's common knowledge at this point that the mountain killed Rhaegar's former lover Elia Martell and the couple's infant children during the sack of King's Landing. But… what if he didn't? That's where young Griff comes into the story.

Tyrion first meets young Griff in the fifth book and later learns that he is actually Aegon Targaryan - the firstborn son of Rhaegar and Elia. Apparently, Varys replaced Aegon with the son of a tanner before the mountain's arrival and smuggled the young prince out of King's Landing and across the narrow sea. He's now planning to reclaim the iron throne and will soon attack Storm's End.

3 Jon Connington

Jon Connington will soon lead young Griff and his forces to Storm's End (Game of Thrones)

Following his arrival in Essos, Ilyrio entrusted young Griff's protection to an exiled Lord called Jon Connington, who also goes by the name of Griff. Jon was a good friend of Rhaegar Targaryen and is one of the very few people who knows young Griff's true identity.

Jon is instrumental in securing the services of the Golden Company and hopes to marry the young prince to Daenerys in order to strengthen and consolidate his claim to the iron throne. He also reaches out to Dorne and many of the Westerosi Lords in the hope of building a large enough army to take King's Landing by force.

2 Arianne Martell

Arianne Martell is the rightful heir to the Dornish throne (Game of Thrones)

Arianne is the eldest daughter of Doran Martell and the rightful heir to the kingdom of Dorne. At least, she would be, anyway, had the writers not cut her and her brother out of the show completely. Given how unpopular the scenes set in Dorne tended to be with viewers though, it's a decision that kind of makes sense.

Doran had originally planned to marry his daughter to Viserys, but after 'the dragon' receives his golden crown, he decides to try and marry his son to Daenerys instead. Sadly, Quentyn's attempt to tame one of Daenerys' dragons leaves him mortally wounded and he dies shortly after. This leaves Arianne as the next in line for the Dornish throne.

1 Aurane Waters

Aurane Waters was captured following the Battle of the Blackwater (Game of Thrones)

Aurane Waters is described as a handsome young man with a similar appearance to Rhaegar Targaryen. He fights for Stannis during the War of the Five Kings but ends up bending the knee to King Tommen after being captured following the Battle of the Blackwater.

Aurane uses his charm and looks to strike up a friendly relationship with Cersei and this, in turn, leads to her giving him a seat on the small council and the position of grand admiral. He's also tasked with organizing the construction of a new royal fleet, although promptly flees the capital with these newly built ships following Cersei's arrest.

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