Steeltrap

Steeltrap is a Deadly Nadder (Franchise) who was fighting in an arena along with another dragons until Hiccup and the riders set them free.

Appearance
Steeltrap's colors are the same as Scardian's with the same injures. His eyes are red.

History
Steeltrap was first seen fighting with Whip-Slash when Ryker was visiting Arena Host.

When Hiccup was captured, Whip-Slash and Steeltrap threatened him but he tell Toothless to not attack them because they're starving, injured and scared. Later, after Hiccup tamed Whip-Slash, Steeltrap try to attack him but Hiccup stayed in the blind spot and scratched the dragon under the chin, conforting him.

After the riders came in rescue and Toothless befriended the Triple Stryke, Hiccup let Steeltrap and the fighter Razorwhip to attack the hunters. Then Steeltrap and the other captured dragons flew free to unknown locations. 

Trivia
* Beside the eyes, Steeltrap looks exactly the same a s Scardian.