Requirements to Unlock: Complete the The Dragon Rider, Part II quest.
Rebuild Snotlout's house.
IMPORTANT: Finishing this quest will permanently unlock Hookfang for purchase in the Book of Dragons / Shop.
For the first 12 hours after completing this quest, this dragon will be discounted by 50%. He will cost 750 . After the 12 hours he will go to his full price of 1,500 .