"This Dragon has been trained specifically to protect Berk's armory. It took over 6 months to stop Knocks from making armor with the swords and shields he was supposed to protect."
―Dragons: Rise of Berk
According to his official description, it was hard training Knocks out of his instinct to wield metal to his body, rather than simply protect a metal stockpile. It is unclear at what age the Hooligans trained him.
Knocks is an Armorwing with a dark green base color and golden-yellow markings on his wings and legs. His armor contains several intact weapons, possibly from the armory stash.