Vhagar is the second biggest dragon after Balerion — an enormous winged beast who died during the Conquest.
As of now, we haven't officially seen Vhagar, even though some fans believe one of the large greyish dragons shown in the first trailers was her. But even if it was, Vhagar's size in the TV show still remains quite a mystery.
We know that technically, Vhagar is the biggest fire-breather in 'House of the Dragon' we will get to see, since Balerion — the dragon ridden by King Aegon I Targaryen during the Conquest — is dead. With a possibility looming that Vhagar will be introduced in episode 5, fans are trying to guess just how huge will she be, given that dragons like Caraxes, Syrax, and Seasmoke have already blown people's minds away with how enormous and fearsome they were.
"Vhagar should be at least twice as large as any dragon we've seen so far. She's like 80 years older than the largest of them (Vermithor)," Reddit user bluelion70 mused.
It has been determined, however, that the TV shows is not always accurate in depicting dragons' sizes. For instance, in 'Game of Thrones', Drogon ended up being way bigger than he was described in the books — something that resulted in many fans being confused when it comes to charts comparing the dragons' sizes.
In the books, Vhagar was described as so large that one could ride a horse down her gullet. It was also said that her breath was so hot that it could melt a knight's armor and fry him from the inside. No living dragon was said to ever match her when it came to size or ferocity.
Needless to say, when Vhagar makes an appearance in 'House of the Dragons', it is going to be a big one — quite literally.
'House of the Dragon' is currently streaming on HBO Max. New episodes premiere every Sunday.