It was impossible for Shen lang to let the giant dragon Destroy the Yan capital. Similarly, the Emperor of Great Yan would not use the giant dragon to destroy the Qian capital even though the Empire of Great Yan did not know that Shen lang had a giant dragon.
Therefore, the great Yan Empire's arrival at Qianjing city was not only to intimidate the great Qian Empire, but also to all the other countries in the world.
Of course, not destroying Qianjing city didn't mean that they wouldn't deal a fatal blow. In fact, there was no need for the Dragon to breathe. As long as the Dragon was in a burning state and flew thousands of meters above Qianjing, it would be terrifying enough.
In the xilun Empire, when the Dragon flew across the sky, the forest on the ground was instantly burned to charcoal, and even the stones were red.