Hiccup discovers that the town's water shortage has been caused by the Outcasts' plan to hide Whispering Death eggs under Berk, which soon hatch and tunnel under the island, threatening the villagers.

The episode was rated 8.00 from 224 votes.

The mysterious theft of metal objects all over Berk reveals the presence of marauding Smokebreaths. Hiccup and Toothless soon discover that these dragons are the work of Dagur, in a plot to render Berk defenseless.

The episode was rated 8.01 from 164 votes.

Hiccup must help Astrid face her fear of the terrifying Flightmare, a ghostly dragon that seemingly "froze" her uncle with fear, shaming her family name. With Fishlegs' help, they discover that there's more to the Flightmare than meets the eye

The episode was rated 8.05 from 195 votes.

When wild dragons start overwhelming Berk, Hiccup and Toothless discover islands are disappearing throughout the archipelago. When Hiccup and Toothless investigate the cause, they then encounter the Screaming Death.

The episode was rated 8.09 from 221 votes.

Snotlout is expelled from the academy; Alvin returns to Berk to make amends.

The episode was rated 8.09 from 163 votes.

Hiccup and co. discover an injured Scauldron on the shores of Changewing Island. The kids must heal the dragon and return him safely to the ocean, before he falls victim to the elements, as well as the territorial Changewings.

The episode was rated 8.13 from 192 votes.

Hookfang and Stormfly quarrel while the town prepares for the harvest.

The episode was rated 8.14 from 170 votes.

The kids go on a dragon survival-training mission to Dragon Island, where they encounter Dagur, the Berserker Chief, who has become obsessed with hunting the Night Fury.

The episode was rated 8.14 from 216 votes.

A Terrible Terror training competition leads to a heated rivalry between Fishlegs and Snotlout, allowing Alvin to kidnap Meatlug. The kids must use their newly trained Terrors to rescue their friend.

The episode was rated 8.17 from 195 votes.

Berk has been plagued with a bad case of the Eel Pox. Hiccup, Toothless and the gang, along with Gothi, go gather the ingredients for the cure. There's just one problem; the final ingredient is an eel from Eel Island.

The episode was rated 8.18 from 177 votes.

Hiccup and Toothless return from a mission to find Berk mysteriously empty. They discover that the village has been overrun by Speed Stingers, a venomous non-flying dragon that has trekked across the frozen sea to Berk.

The episode was rated 8.18 from 190 votes.

When the dragon riders discover a frozen Skrill, a lightning-powered dragon revered by the Berserkers, they scramble to get it off Berk.

The episode was rated 8.20 from 189 votes.

While searching for traps, Tuffnut, Barf and Belch get trapped themselves... and a forest fire is approaching.

The episode was rated 8.28 from 193 votes.

Tuffnut goes undercover to help the riders rescue a Skrill.

The episode was rated 8.31 from 171 votes.

Alvin reveals he trained the Screaming Death to attack Berk and destroy the island's inhabitants and only Snotlout and Hookfang can save Berk before it's too late. Meanwhile Hiccup gets ready for a final fight against Dagur to save Toothless and end the barbarians invasion of Berk once and for all.

The episode was rated 8.48 from 162 votes.