Fangmaster

"As awesome as Hookfire, Fangmaster and Hook Blazefang are... and I named them all already, I can't look at them and not think of Hookfang."

- Snotlout naming the three dragons

Fangmaster is a Monstrous Nightmares that Snotlout named when the other Dragon Riders tried to find a replacement for Hookfang.

Description
"The Riders found Fangmaster for Snotlout, to help get his mind off the absent Hookfang. It turns out Snotlout would rather go dragonless than ride another Monstrous Nightmare."

- Dragons: Rise of Berk

Replacements for Hookfang
In "Total Nightmare", Hiccup thought that Snotlout needed a replacement dragon when Hookfang "ran away". When Hiccup brought in Fangmaster, Snotlout named him after Hookfang and rejected them.

Physical Appearance
Fangmaster is multi-colored, being pink, blue and yellowish-green.

Trivia

 * Fangmaster's coloring resembles that of Hookfang's mate.