When Trader Johann delivers mass quantities of metal to Berk that came from Breakneck Bog, the island becomes infested with Smothering Smokebreaths, that steal the town's metal to build a new nest. With no metal, and especially no weapons to protect their village, Hiccup and the others must find a way to get rid of the rogue dragons, only to discover that the Smokebreaths' appearance was planned as an attack by Dagur the Deranged.
Tropes:
- A Rare Sentence: Uttered by Dagur when Hiccup delivers the scrap metal to the Berserkers: "Could this be the spoon of surrender?" Savage can only respond, "I don't think so, sir."
- Batman Gambit: Dagur and the Outcasts dropped the scrap metal in Breakneck Bog, knowing that Johann would pick it up and that Smokebreaths were invading it.
- Big "NO!": Tuffnut when Macey is taken.
- Boring, but Practical:
- The scrap metal pile that starts the episode. Gobber takes it because the smithy can always use scrap metal.
- Dagur's plan, actually: get Johann to deliver a pile of scrap metal to Berk infested with Smokebreaths. Without metal, or so he thinks, the Berkians will be weaponless and will lose in a Curb-Stomp Battle with the Outcasts.
- Call-Back: Once more, the Smokebreaths try to steal Hiccup's prosthetic.
- Cargo Ship: In-universe. Tuffnut's obsession with his new mace (nicknamed "Macey") is actually somewhat disturbing.
- Even the Dog Is Ashamed: Everyone walks away from Johann in disgust when he chooses to keep telling his story rather than acknowledge that this incident is partially his fault. Toothless hisses at him before leaving.
- Everyone Has Standards: Ruffnut refuses to be associated with her brother's obsession over his new mace.
- Glad I Thought of It: Dagur's plan was actually Savage's idea, but Savage isn't going to argue about who came up with it.
- Hoist by His Own Petard: Dagur's plan backfires when Hiccup uses the remaining metal to lead the Smothering Smokebreaths to his fleet, and drops the pile, causing the dragons to grab all the metal available and effectively destroy the entire fleet.
- I Call It "Vera": Tuffnut's mace, Macey.
- Laser-Guided Karma: Johann may have not intended to bring chaos to Berk, but he could at least have apologized instead of waving it off by basically saying "Oh what a shame." So of course, he's saddled with getting the Smokebreaths back to Breakneck Bog at the end.
- I Kiss Your Foot: Dagur swears Hiccup will do this to him one day, as he floats away, defeated.
- Murder the Hypotenuse: When Macey goes missing, Tuffnut accuses his sister of doing this.
- Shamu Fu: With their bludgeons missing, Bucket and Mulch take to slapping each other with sturgeons. Later, before the Riders come in with the Smokebreaths, the two were armed with sturgeons to defend Berk from the invading Berserkers.
- Skyward Scream: Tuffnut's above mentioned Big "NO!" is one of these.
- Wind from Beneath My Wings: Toothless uses this again in Hiccup’s room, like the previous appearance of the smoke monsters, used this to blow away the smoke revealing the Smokebreaths.
- Unwitting Instigator of Doom: Johann when bringing a pile of scrap metal from Breakneck Bog ends up enabling the Berserkers and Outcasts to disarm Berk indirectly. Subverted as, after he was revealed to be Evil All Along in Season 7, this might have been the plan.
