The Red Witch
"Yes, he and I go way back. At first, he was wary of us, but we taught each other about ourselves after meeting him. It helped us understand each other more and because good friends. He even convinced most dragons to be friends with humans."
"Wow, I never knew."
"That is until Elderon, younger than Gorik, wanted to end humanity and rebelled. There was an all-out war between them. It was known as The End because people feared that the war between two dragons would end the world. Many dragons died, which is the reason why dragons no longer exist except for Gorik and Elderon."
I never saw something like that happen way back before any of us were born. It's not in the books or stories mentioned.