Here's an interview with Dean DeBlois and sound designer Randy Thom about what it took to create the sounds of the dragons in How to Train Your Dragon 2!
With its diversity of dragons, How to Train Your Dragon 2 has a lot of opportunities for great sound momenents. Sometimes, getting a sound that matches a dragon requires recording and mixing real-life animals. Other times, it requires Randy Thom.
Thanks, Aty S Behsam!