What is vhagar vs balerion?

Vhagar and Balerion were both dragons in George R.R Martin's A Song of Ice and Fire series.

Vhagar was a dragon ridden by Aegon I Targaryen's younger sister Rhaenys during the Targaryen Conquest of Westeros. Vhagar's color was dark green and she was one of the largest dragons of her time. She lived for over one hundred and fifty years and was eventually killed by another dragon, during the Dance of the Dragons civil war.

Balerion, also known as the Black Dread, was ridden by Aegon I Targaryen himself during the Targaryen Conquest. He was the largest and oldest dragon known in the history of Westeros and was known for his black scales and red eyes. Balerion's flames were hot enough to melt locks and walls of a fortress. He died of old age in the reign of King Jaehaerys I Targaryen.

In terms of comparison, both Vhagar and Balerion were powerful and formidable dragons. However, Balerion was larger, older, and more powerful than Vhagar, making him one of the most legendary dragons in the history of Westeros.