The Game of Thrones franchise and the Targaryens are back under the mainstream spotlight thanks to HBO's House of the Dragon, and it was Daenerys Targaryen who helped popularize the dragonlord family. Emilia Clarke's performance made the character an icon of George R. R. Martin's A Song of Ice and Fire adaptation by showing her determination to reclaim her family's throne.
And barring the panned final season, the flagship show was widely acclaimed, but even so, it was done with some tweaks to the source material. From the age of both continuities' iterations of the character to an entirely new blood relative, there were some noteworthy differences between Daenerys in the books and the live-action show.
Daenerys Was Younger In The Books
The characters' age was one of the broad changes in Game of Thrones. Like the Starks and Lannisters, Daenerys was notably aged up from her character in A Song of Ice and Fire.
It could have been a creative choice to make the cast more palatable, as it might have been even harder to see the events of the live-action show play out with a cast of so many children as main characters. In the books, Daenerys is introduced to be around 13, while the show starts her off at around 17 years old.
The Targaryen Violet Eyes
One of the more popular facts that Game of Thrones book fans will know is the omission of the Targaryens' violet eyes. It was never strictly violet, but the Targaryen family had eyes that varied across different shades of purple. Even now with House of the Dragon depicting a time when the Targaryens were prominent in Westeros' hierarchy of power, it's a change that's stayed across the live-action canon.
It would have been a nice visual touch to see in the show for longtime fans, but it's an admittedly minor one. However, as noted by Den of Geek, this was a logistical choice since violet contacts were deemed too uncomfortable to wear.
The Other Targaryen Nephew
In a much more dramatic change from the source material, Game of Thrones was known to leave out entire characters with important roles in the books' stories. Many fans will also point out the likes of Lady Stoneheart, the reincarnation of Catelyn Stark as a vengeful undead, but the show also cut out another Aegon Targaryen.
Another Targaryen nephew of Daenerys named Aegon, this version came before the fan-favorite Jon Snow (who is technically Aegon VII, not VI) and would actively challenge her claim to the Iron Throne. Nicknamed "Young Griff," he was the son of Rhaegar Targaryen and Elia Martell, and despite being killed before the show's events, he was smuggled out of Westeros in the books.
Her Vision In The House Of The Undying
In Game of Thrones season 2, Daenerys finds herself and what remains of her support from the Dothraki desperate for help in the city of Qarth. The most notable event to arise from this storyline is when the warlock of the House of the Undying kidnaps her dragons to lure her into a trap. In the books, however, both the context and substance of her visions were different.
Daenerys is formally invited to visit, and she accepts willingly, entering the House of the Undying with Drogon by her side. Likewise, the visions she sees are even more foreboding than seeing a ravaged throne room. For instance, she's alluded to the Red Wedding, sees Rhaegar make a prediction surrounding the prophecy of the Prince that was Promised, and hints at Rhaegar and Lyanna Stark's relationship.
How She Tamed Drogon
Daenerys flying on Drogon for the first time was one of her best moments as a character in Game of Thrones, but the context surrounding how this happened in the books was different. The crux of this event in the show was the attack of the Sons of the Harpy at the Fighting Pits.
The books depicted no such attack, and it was the smell of blood that attracted Drogon back to the pits. After a combatant attempts to kill him, Daenerys leaps to his aid, but the dragon turns to her like she's his next meal. It was then that she realized she needed to tame him, leading her to crack a whip at Drogon until he understood.
Her Fire Immunity
Something that's noted in the books and lore that was exaggerated in the show was her resistance to fire. In Game of Thrones, she's portrayed more than once as being outright immune to it, namely in the season 1 finale when she emerges from the funeral pyre with three freshly-hatched dragons.
But in the books, Daenerys, and the Targaryens in general, aren't immune to fire. Rather, they specifically have a high resistance to it. Daenerys being able to walk away from the pyre unharmed in the books was a result of the blood magic cast by the witch Mirri Maz Duur. So while fire is something low on the Targaryens' list of worries, it's also not something to shrug off.
The Kidnapping By The Khalasar
Following Daenerys' escape from the fighting pits of Mereen on dragonback, she ends up being kidnapped by a roaming Khalasar. She was left exposed when Drogon was recovering from his wounds. In A Dance with Dragons, a Khalasar scout doesn't notice Daenerys as she's left hallucinating in the grass after eating a bad batch of wild berries.
She then sees a vision of Ser Jorah Mormont that inspires her to pull herself up, call Drogon back to her, and fly to the Khalasar herself in a show of power where she reminds them who ate the horse's heart and hatched three dragon eggs. Rather than a kidnapping, this turn of events was far more assertive on Daenerys' part in the book. This is one example of the source material's overall portrayal of Daenerys as an aggressive survivor.
Varys Wasn't In Daenerys' Corner
Since Game of Thrones cut out the book series' version of Aegon VI entirely from its respective canon, some of the allegiances from the source material were naturally changed in the show. The reason Aegon VI survived being killed by The Mountain in the continuity of the books is that Varys swapped him out with a commoner's baby to sacrifice, smuggling the Young Griff to Essos.
Varys is a Targaryen loyalist, but specifically because he backs Aegon's claim to the Iron Throne rather than Daenerys'. He's a direct opponent to her instead of an advisor and supporter. In a way, Daenerys has less of an advantage in the books than her show counterpart.
She Was Deeply Infatuated With Daario
While the show depicted the relationship between Daenerys and Daario Naharis much more casually -- namely with the former -- the dynamic was heavily reversed in the books. Likewise, Daario isn't presented as the charming swashbuckler that the TV adaption went for. Instead, Daenerys was deeply infatuated with him, obsessively thinking about him more often than not.
Meanwhile, Daario was murkier as a character and disconnected from her outside of superficial reasons. Daario represented Daenerys' darker impulses since he encouraged her to be more tyrannical.
She Was More Consciously Pacifistic
Game of Thrones did portray Daenerys trying to opt for peaceful resolutions to conflicts when she felt she could. At the same time, though, there were other instances where she was rather quick to choose the violent option -- even before her drastic turn into outright authoritarianism in season 8.
Daenerys is almost obsessively conscious of her violent impulses in the books, fearing that she'll turn out just like her father Aerys II, the "Mad King." That mindset is what led her to be far more pacifistic (for better and worse) when faced with a sensitive problem.