In the 3rd film Hiccup & Astrid fight a new villain out to destroy dragons & then decide they must take them to a hidden land for safety.
The Congress (2013)
A fading actress agrees to be scanned so that her digital image can be used by the studio to make films she would have refused. Years later, regretting this, she goes to the Animation Zone in search of her lost son.
Cloudy With a Chance of Meatballs 2
Inventor Flint Lockwood and his friends go back to his island to combat the menace he thought he had destroyed in the first film, his Diatomic Super Mutating Dynamic Food Replicator before it can wreak havoc again on the world.