Hiccup narrating "Legends speak of a legendary dragon...one that most think doesn't even exist. It's called...the Mutantlator. It's a monstrous dragon that's said to have the abilities of every dragon in existence, both discovered and undiscovered, Bork the Bold mentioned the Mutantlator and in his words, he describes it as "Death incarnated as a dragon". No one has ever lived to describe what the Mutantlator looks like since, much like the Night Fury, it never steals food, never shows itself, never misses but it also...never leaves anyone that sees it alive".

One day, Hiccup, Valka and the other ridders were off rescuing dragons from hunters when they heard some hunters getting lectured by who looks like their commander.

"OK...remember, there's no point in trying to shoot it down, so if you hear it, get to cover and stay hidden until your sure it's gone" he said to five of his men.

"Has anyone ever tried to shoot it down" one hunter asked.

"No because, 1, it's as fast as a lightning bolt and 2, it can stay invisible while flying, so technically it's impossible to hit it." the commander replied.

"Is there even...any proof that the Mutantlator exists?" one hunter asked, to the dismay of Hiccup and his friends.

"The Mutantlator? What's that?" Snotlout asked.

"I don't know but it sounds cool." said Tuffnut.

"It's a long story...it's essentially a legendary dragon, one that many don't even think it's real." said Hiccup.

"It's a dragon that's said to have the abilities of every dragon in existence, both discovered and undiscovered" said Valka.

Everyone was in awe. "But, there's never been any proof of it and most think that it doesn't even exist and someone made it up" said Hiccup.

"Awe" Tuffnut sounded disappointed.

"Anyways, everyone get ready" said Hiccup.

As they were getting ready to strike...they heard it. What sounded like a Night Fury charging up a Plasma blast.

"MUTANTLATOR" a dragon hunter yelled!

"Everyone get to cover" the commander yelled as they all ducked behind barrels and dragon cages.

And then...

BOOM!

One of the ships explode in a fiery explosion as a large black shadow, moves past the explosion at lightning speed. Hiccup and the others were just in awe. Snotlout was speechless, the twins were amazed, Hiccup, Toothless, Valka, Astrid and Fishlegs were in shock of what happened. A legendary creature, once thought to be a joke, was actually real. Then, they hear another shot charging up...

"Here it comes again, brace yourselves and keep your eyes open" said Hiccup just as the second charged shot hit another ship.

They see the large shadow fly by again and their gaze follows it but it disappears out of sight.

"I tried to follow it with my eyes but it's so fast I can keep up with it" said Tuffnut.

"Yeah Hiccup, I feel like if I blink it'll be out of sight" said Astrid.

Hiccup took a deep breath and said "Come on"...as they jumped on their dragons and joined the fight.

They ended up freeing all the dragons just as the 3rd and final shot from the Mutantlator hit the last ship. While Hookfang fell backwards from the impact of the 3rd shot, Snotlout fell backwards in the water, Hookfang went to go get the others as Snotlout swims to the surface. Just as he was about to get out a black long tail grabbed him and pulled him out of the water and helped him to the docks.

"Thank you Hookfa..." before Snotlout could finish he looked up and was shocked and horrified at what he saw...a masked hooded figure, riding the legendary dragon of death itself. He wiped his face and got a good look at the Mutantlator. It looked like a buff Night Fury, but stood as tall as a Monstrous Nightmare, it had 4 gigantic wings with 3 long tails, that were covered in spines.

"Snotlout?" Hiccup called out to him from the smoke. The Mysterious Rider & the Mutant looked in that direction then back at Snotlout, the mutant formed it's 3 tails into 1 big tail then took off high in the sky in a flash. Snotlout just stares up at where the 2 went when Hiccup, Toothless and Hookfang showed up. "Come on Snotlout. Snotlout? Snotlout!" hiccup shouted at him, snapping him out of his trance.

"Sorry, I...I..." before he could finish Hiccup cut him off and said "You fell in the water, I know".

He grabbed his hand and pulled himself up. "Come on, we're done here" Hiccup said as he got on Toothless and Snotlout got on Hookfang.

They all left towards Berk, before Ruffnut and Tuffnut saw something that made them stop Barf & Belch. "Oh...my Thor" said Tuffnut.