Caraxes

Vhagar died fighting Caraxes the Bloodsucker on the Eye of God. In my opinion, this was a battle between the two most powerful dragons alive during the Dance of the Dragons, the first mounted by Prince Aemond Targaryen and Prince Daemon Targaryen.

Between dragons and men, only Daemon could have survived, and we can only say that because his body was never found; It may have been lost. Caraxes was the smallest dragon, but he seems to have had an advantage over Vhagar, but not enough to kill her and live.

Both dragons finally died, already mortally wounded before touching land. Caraxes is a dragon that could, like Sheepstealer, have a great future ahead. Had Caraxes lived, it would have been the most powerful dragon alive and could have lived easily for many decades or even a century or two.

It could have been the dragon that avoided the Dungeon Assault, but it could also be he who drove the Targaryens to the throne. But that story was not going to be like that. And there is at least one dragon that would not have had any problem with Caraxes.

Balerion

As with Drogon, there’s not much I can say about Balerion the Dark Terror that you do not know yet. Probably inspired by Ancalagon the Black, the largest of the winged dragons of Tolkien’s Legendarium (another of George RR Martin’s dragons is called “Morghul”), Balerion was big enough to swallow an entire uro. Balerion is the most important factor in the success of the conquest of Aegon; That should be more than enough reason to put it at the top of this list.

Even before the Conquest, Balerion achieved much, including the destruction of the Volantis Fleet, a feat that Drogon might be forced to replicate. During the invasion of Aegon, Balerion destroyed Harrenhal, killing Harren the Black Hoare and their children and melting parts of the huge castle, including what would later be called Kingspyre Tower.

Balerion was not a young dragon when Aegon the Conqueror landed at the place that would become King’s Landing. Unlike Vhagar and Meraxes, Balerion was born before the Curse of Valyria, the only dragon on this list other than Terrax for whom that is true. Maybe that’s why he is in a league. It is obvious that knowledge about dragons deteriorated over the centuries after the Curse.

And as the knowledge withered, so did the dragons, to a certain extent. In a way, looking at Balerion is like looking back in time; What was the world like when dragons the size of Balerion were the norm? He is up and apart.