I have a question. If he has to learn how to fly, why doesn't he need to learn to speak and understand dragonesse or whatever the dragon's language is called? I've only seen one HTTYD dragon transformation story where someone who got turned into a dragon had to learn that.

Excellent question, the answer is simple, but explaining it would count as spoilers, however I can tell you that the encounter between the Dagur and the T.T was not something random and that it was needed that they could understand each other, so the power to talk their language was given to him, why? Well you will see it in the story

I see. In my HTTYD stories that I've started to write that involve dragon transformation, I avoid the language problem by having the dragons be 'logopathic' with telepathic broadcasting capability that only other dragons can receive and to a much lesser extent humans that are bonded with them. Basically, they are telepathic but their telepathy is limited to understanding the language of others and broadcasting their thoughts to others. Its a concept I got from The Heart Bind Saga ( https://archiveofourown.org/series/956436 ).

Wow. you're doing a great job on this!

Thank you!