The Riders race to the home of the true King of Dragons. But the Flyers are already there, and they soon come face to face with the legendary creature.

After learning several Flyers followed Heather to Vanaheim, the Riders must stop them from reporting the sacred island's location to their leader.

With the fifth lens in place, the Dragon Eye 2 unveils the apparent King of Dragons, and Fishlegs immediately knows what it is and where to find it.

While hunting for gemstones needed to complete the Dragon Eye 2, Hiccup learns an old friend isn't who he seems. Dagur faces a bully from his past.

While on night patrol, Stoick is ambushed by the Flyers and gravely injured, leaving Hiccup torn between his duties as a son and as the Riders' leader.

Stoick and Hiccup are led on a wild goose chase in search of willow bark for medicine, leaving Berk vulnerable to an enemy attack.

When the Flyers try to kill him because he's no longer useful, Viggo forces Hiccup to help him get revenge by stealing their Dragon Eye and lenses.

An unlikely ally helps Hiccup uncover Singetail behaviors that can be exploited to conquer the Flyers. An overconfident Krogan makes a strategy error.

While rescuing the dragons from a fire in the stables caused by a powerful lightning storm, Astrid suffers an injury that leaves her blind.

The Riders learn of Ryker's attack on the Edge and attempt to stop the Shellfire and keep the Dragon Eye from being reclaimed by the Hunters.

An announcement leads Astrid to question her relationship with Hiccup. The Riders discover an Armorwing that has a Dragon Eye lens welded to its body.

The dragon riders are surprised to discover who is behind recent attacks on nearby ships – and to learn exactly what the ships are.

Hiccup grows wary when Gruffnut arrives on the twins' 19th birthday to administer a Thorston coming-of-age ritual involving three dangerous challenges.

When Hiccup and Toothless are kidnapped and Toothless is forced to fight other dragons for entertainment, the rest of the dragon riders must save them before it's too late.

Upset after learning his ancestors were Hunters who killed off Dramillions, Fishlegs sets out to see if he can find any of the dragon species left.

When Viggo offers Hiccup a truce, the wary Dragon Riders investigate and find a potential ally in their fight against the Dragon Hunters.

Heather's brother Dagur shows up out of no where and asks Hiccup for help finding her. He wants to learn to ride dragons. Dagur sees Heather on the edge and goes the extra mile to protect her.

Hiccup, Toothless and the dragon riders journey to Glacier Island in search of the Snow Wraith, a fearsome new dragon that holds the key to the Dragon Eye's mysteries.

When Hookfang is drawn to a female Monstrous Nightmare, Snotlout tries to break them up before he loses his best friend forever.

Viggo gets angry at the dragon riders continually interfering with his business and uses a deep sea dragon, the Submaripper, to control Berk's trade.

The Riders flee to Berk, where Stoick's plan for defeating the Flyers, which will require a painful sacrifice, spurs Hiccup to seek an alternative.

The Outcast leader, Alvin, is kidnapped and held for ransom by bandits. They call on the Dragon Riders to request the assistance of Thor Bonecrusher.

After months of planning, Hiccup launches an operation to capture the Dragon Eye from Viggo, only to find that someone else has beaten them to it.

When Ruffnut refuses to become Throk's bride because it would mean leaving her twin, Tuffnut fakes his own death to give her the freedom to marry.

Thinking he's allergic to his best friend Meatlug, Fishlegs gets hypnotized – and wakes up transformed into an invincible warrior known as Thor Bonecrusher.

After a strange creature bites Tuffnut, he believes he'll turn into a legendary Lycanwing dragon when the moon is full. Can his friends save him?

When things don't go well while Fishlegs is in charge, he gets another chance to prove he has what it takes to be a leader.

When the Twins journey to the Northern Markets to fix their prized mace, they end up stumbling onto a secret project by Viggo and the Dragon Hunters.

When Snotlout is rescued from a storm by a tribe of winged women, he thinks he's gone to Valhalla -- until he learns he's going to be their dinner.

After getting bad advice from his father, Snotlout tries to seize leadership of the Dragon Riders and starts making reckless decisions on his own.

Hiccup and the Riders, with help from Dagur hatch a plan to steal Berk's gold back.

Fireworm dragons invade Dragon's Edge, while Ruffnut and Tuffnut discover that they have an unexpected connection to the island.

Snotlout and Astrid must deliver a special battle axe to a family wedding, but when an Armorwing dragon derails their plan they have to work together.

After Hiccup and Toothless heroically save Barf and Belch, the grateful Zippleback tries to repay its life debt by abandoning riders Ruff and Tuff.

Disobeying Hiccup, the twins follow a retiring Eruptodon to its final resting place, Vanaheim, and learn why no human has ever gone there before.

When Dagur the Deranged captures young Gustav, it's up to Hiccup, Toothless and the dragon riders to get him back.

A sketch in an old diary leads Hiccup and Fishlegs back to Vanaheim, where they help Dagur search for his long-missing father, Oswald the Agreeable.

When a new tidal class dragon, the Sea Shocker, is found in Edge Cove, the riders must help it escape a group of hungry Scauldrons and reunite it with its migrating pod.

Hiccup, Toothless and the dragon riders rescue a wounded Speed Stinger and take it back to Dragon's Edge, unaware of the dangers that follow.

When a mysterious dragon attacks Spitelouts storehouse, Spitelout and Stoick have different ideas on what to do next.

While trying to stabilize the volcano that threatens to destroy Dragon's Edge, the Riders discover troubling evidence of new Hunter activity.

When the Dragon Riders fly to an island on a vacation, a small creature there has a special effect on the dragons.

When Ruffnut is captured by Dragon Hunters, it's up to Astrid and Tuffnut to defend Dragon's Edge from the invading Dragon Hunter army.

After Stormfly tangles with two poisonous Slitherwings while defending Garff, Astrid must risk her own life to get an ingredient to make an antidote.

After learning that Fishlegs has been secretly communicating with Heather, the gang invites her to the Edge to convince her to join the Dragon Riders.

Fishlegs and Meatlug liberate the Gronckles from a menacing new dragon that has encroached on their ancestral home, Dark Deep.