How to train your dragon: The New Adventure

After Zephyr and Nuffink visited the dragons with their parents, Toothless, Lightfury and Nightlights have been coming to new berk every once in a while. When they were playing in the woods Dart found a secret entrance to the hidden world on new berk.
But then a new enemy comes, who wants to find the hidden world. He claims to have seen dragons.
Hiccup and Astrid are captured. Now it's up to Zephyr, Nuffink, Dart, Pouncer and Ruffrunner to save them and protect the hidden world.

I do not own How To Train Your Dragon.
The art on the cover is not mine.

Set after Homecoming and httyd 3.
Zephyr is 9, Nuffink is 6.