Quick recap
It's Berk's first Snoggletog with dragons, and the village goes all out. Suddenly every dragon takes off and leaves without warning. Only Toothless stays, because he can't fly without Hiccup. To give him freedom, Hiccup builds a new tail fin that works on its own, and Toothless flies off after the others. Hiccup follows and learns why they left: the dragons went to lay eggs on an island. They return to Berk with their hatchlings, the holiday takes on new meaning, and Toothless makes it clear he'd rather fly with Hiccup.
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