It is written under the strike class for its ability to ride lightning bolts like air torpedos, intelligence, and jaw strength. This elusive dragon has large wings, a spiked back and tail, and a large mouth. The spikes on the Skrill's back and tail are sharp enough to cut with the slightest abrasion, and it is an excellent flyer. It apparently resembles a Night Fury in flight and rivals its speed, being slightly slower. Like the Monstrous Nightmare, its locomotion on land resembles that of a pterosaur, using the large claws on its wings to walk and run on land.
As with most of the dragons in the manual, it is listed as being "extremely dangerous" and the manual instructs readers to "kill on sight". It slightly resembles a Thunder Drum, and its head also resembles that of a Deadly Nadder. When a Skrill is riding lightning, it seems to wrap itself in its wings and dive down.
Defenders of Berk
In "A View to a Skrill Part I", A Skrill was found trapped in an iceberg by the Berserkers. Bucket and Mulch, who thought the Berserkers had crashed into an iceberg, came to help until they saw the Skrill. The Berserkers then fought Bucket and Mulch and were easily overpowered by the duo. The dragon riders arrived and the Berserkers retreated. Mulch then showed Hiccup and his friends the frozen Skrill. The dragon riders took the frozen Skrill back to Berk and placed it inside the Dragon Training Academy. The Skrill was later freed by Barf and Belch and Ruffnut and Tuffnut. The dragons and their riders try to keep the Skrill caged in but it managed to escape into the wild. The Skrill flew into the dark clouds where it charged itself with lightning. The Skrill then fired it's lightning breath at the dragon riders before fleeing into the clouds. Toothless and Hiccup managed to lure it out of the clouds by firing Toothless' plasma bolts at it. Astrid and Stormfly and Hiccup and Toothless and Ruffnut and Tuffnut and Barf and Belch then attack the Skrill. The Berserkers attacked the dragon riders as well. The Skrill attacked Snotlout and Hookfang from behind with it's lightning breath, striking Snotlout in the head. The Skrill flew into the clouds when the dragon riders decide to regroup. Later, Ruffnut and Tuffnut lure the Skrill out of the clouds by using Barf's gas and Belch's electric spark to create a powerful explosion. Toothless fire his plasma bolts at the Skrill but it blocks them with it's lightning breath. It then chases Toothless and Hiccup, firing it's lightning breath at them. Barf and Belch fire at the Skrill, causing it to chase them. The Skrill fires it's lightning breath at Barf and Belch but Toothless blocks the shock with a plasma bolt, causing an explosion that blasts all three of them out of the sky. The Skrill then falls into the ocean, where it is vulnerable. Alvin and the Outsiders capture the Skrill, hoping to train it back on Outcast Island.
In "A View to a Skrill Part II", the Skrill is taken to Outcast Island where Dagur and Alvin make a deal with each other. Alvin will help Dagur get the Skrill and Dagur will be given it after he helps Alvin destroy Berk first. However, Dagur betrays Alvin and steals the Skrill from it's cage and takes it to his ship. Alvin finds out and angrily fights Dagur. Alvin has the upper hand at first but Dagur then uses the Skrill on him. Alvin jumps into the sea and Dagur uses the Skrill to shoot lightning at the water, seemingly killing Alvin. Dagur uses the Skrill to battle Hiccup and Toothless. The Skrill blocks all of Toothless' plasma shots but when Dagur steps into puddles of water, Toothless fires a plasma bolt that causes the Skrill's electricity to shock the Beserker. The Skrill then chases Hiccup and Toothless into an iceberg where he is knocked out by an ice wall after charging at Toothless and Hiccup's reflections that he thought were real. Ruffnut and Tuffnut and Barf and Belch then seal the ice berg, causing the Skrill to be frozen again.
- The Skrill logo appears on Dagur's boat. The logo also appears on Dagur's belt. meaning that the Skrill is the Berserker Crest.
- At full speed, the Skrill is the second fastest dragon in the dragon world, with the fastest being the Night Fury.
- The Skrill has an error on it's official page (in the gallery). Instead of saying it is in the Strike Class, it is labeled as being in the Sharp Class.
- According to the Cartoon Network site, Skrills are completely untrainable.
- The fact that Skrills only show during electrical storms could indicate a fear of cloudless days and the sun.
- The Skrill's favorite food is sheep.