Nice chapter. Will any more classic who villains (or new villains) make any appearances?

Nice Chapter. Please continue

Great Chapter. Will Hiccup and the Dragon Riders encounter any of The Doctors classic foes like the cybermen, the master or the mara? Also will they go into the Tardis and meet Kamelion?

That was really cool.
That was quite a first encounter with beings from outer space for Hiccup and Toothless, not counting the Doctor.
Odds being good that the Doctor will know the name of their race.
That's what I think.
Wonder if he'll have a theory of why they're after dragons as well.
This story's going great so far.

I like this idea. Clearly for the Doctor and Turlough this is set just before planet of fire. But, when does this take place in how to train your dragon franchise. I mean its clearly after the first film but is this set in the show or one of the sequels?

Please let Astrid interact with The Doctor and Turlough in the next chapter

After reading what there is of this story to read, I am hoping very much it will continue to continue.
Very nice work.

OMG, great crossover idea. I wonder what the Doctor will do in all three movies and tv show