What is the name of a mount in World of Warcraft that looks like a star (like a constellation) but is a constellation dragon?

It's called the Star Dragon. As for other mounts, you can buy them with prestige, lost copies and direct grades. The simplest mount is an ordinary mount that can be purchased with rank, and then purchased with prestige. You can buy it from the quartermaster as long as you have prestige. What is not easy to obtain is the lost copy, and the loss rate is limited.