I know it's been a long time since this was written but I figured you guys deserved to know what would have happened.
- In Chapter 11, Stoick would have finally been told the truth about Astrid's pregnancy as well as Astrid's parents. Stoick would have been happy, but also scared on how the village would react. Astrid's parents would have been supported. Also in that chapter, Hiccup is in denial about Astrid's pregnancy and becoming a father until he broke down during a fight with Dagur, letting Dagur comfort him as he comes to terms with the fact he got Astrid pregnant and he's going to be dad to a child he will probably never see. Dagur brings the fire and motivation back into him to escape and reunite with Astrid and their unborn baby. At the very end, Viggo talks with Ryker about how everything is going to plan and how he knew Astrid was fertile when he kidnapped her.
- The rest of the story would have gone like this.
- Hiccup and Dagur attempt escape, but fail miserably and get caught, causing Viggo to take Ember away and kill her in front of Hiccup. Meanwhile Astrid starts making a nursery on the Edge, refusing to believe that Hiccup is gone for good, and as she gets tired and needs a break, she sits with Toothless and tells her unborn baby about Hiccup befriending Toothless.
- After Hiccup and Dagur try to escape a second time, Viggo taunts Hiccup about how his spies have noticed Astrid talking to the unborn baby with so much hope that he's alive and going to come back. After Hiccup flips him off, Viggo cuts off Hiccup's middle finger and sends it along with a note to the Riders to make it seem like he has killed Hiccup. Astrid collapses with grief and so do all the Riders. As they discuss what to do, the baby kicks inside Astrid for the first time and all the Riders promise to protect the unborn child with their lives, their last piece of Hiccup.
- Planning a third escape attempt, Hiccup has nearly gone mad, so determined to get to Astrid and the baby. He makes Dagur promise that if he dies trying to get out of the prison, he'll protect his offspring with his life as their uncle. Dagur is both touched and heartbroken, but agrees. Meanwhile, Stoick is told about Hiccup's "death" and goes on a rampage, vowing to kill Viggo. Viggo however, excitedly tells Ryker that Astrid is only a month away from giving birth and they need to prepare, revealing that he's got guards crafting a crib on one of his auction ships.
- Astrid's birthday rolls around and the Riders all give Astrid baby gifts. It's a wonderful day for everyone until Astrid opens her final gift, which is a Maces and Talons piece with a note in Viggo's handwriting, "I can't wait to meet the little one". This makes everyone paranoid and security on the Edge is doubled.
- As Hiccup and Dagur attempt their third escape, it almost works until they get trapped. Knowing that Hiccup should have a chance to be with his lover and child, Dagur sacrifices himself to the guards as Hiccup gets out from the prison and gains the trust of a Hotburple he names Bumpy. Quickly flying away, he realizes that he has no idea how to get to the Edge and lands on a friendly island, stopping there to heal and accept that Dagur is dead. He writes a heartfelt letter to Astrid, telling her that he misses and loves her and can't wait to meet their child. When the letter comes to Astrid via Terrible Terror, she cries in joy and dances around the room with Toothless, her beloved Hiccup alive.
- As Viggo directs a course to the Edge, the Riders celebrate the fact that Hiccup is alive. Shortly after celebrating though, Astrid feels contractions and has to lay down. As this begins, Viggo approaches the Edge with several ships filled with guards. Knowing that the situation is dire, Fishlegs stays with Astrid and tries to help her as she starts labor, and Heather flies out to find Hiccup. And quick. Astrid sends a prayer to the gods, praying that Hiccup be there for the birth of his child.
- As Hiccup is in the village he landed in, he notices a Maces and Talons game in a stall. He looks at it and ponders it, playing with the pieces until he realizes that Viggo wanted this all along, and that his and Astrid's child is in danger unless he gets there. As he realizes this, Heather shows up and tells him that Astrid is in labor. As they rush there, Viggo slowly makes his way through the Riders, and gets to where Astrid is, knocking Fishlegs out and taking Astrid onto his boat as her contractions get worse.
- Hiccup and Heather reach the Edge, only to find that Astrid has already been taken. They find the ship, and Hiccup shares a heartfelt moment with Astrid and reunites with her before being taken by Viggo. He reveals that he plans to take the baby and sell it at auction as "The Dragon Master's Offspring" for an absolute fortune, not only upgrading his trappings and weapons to fully destroy the Riders and all of Berk, but breaking Hiccup and Astrid by making sure they never see their child again. Enraged and desperate, Hiccup resorts to Toothless completely destroying the ship with no mercy, managing to grab Astrid with Heather as the ship sinks and Viggo clings to a piece of floating wood, vowing to get revenge. Almost to the Edge, Astrid tells them to land NOW and that the baby is coming. Getting to the beach on the Edge, Heather and Hiccup work together to help Astrid, and the baby is born. Hiccup happily tells Astrid that they have a daughter.
- As Hiccup and Astrid look at and admire their small daughter, they properly reunite and share a long kiss. Astrid cries as she tells him that she thought he was dead, and Hiccup reluctantly tells both her and Heather that Dagur is dead. That he sacrificed himself for Hiccup and the baby in Astrid's arms. As they talk about a name, Astrid comes up with Dagny, a name that means "A new day" and also honors Dagur's sacrifice. Hiccup agrees that it's perfect and the next morning they show off baby Dagny to the other Riders. In the epilogue, Dagny (red hair like Stoick, green eyes like Hiccup, round face and ears like Astrid) is three years old and Hiccup and Astrid have been married for three years, marrying shortly after Dagny's birth. (references to the second and third movie during their conversation) Astrid is pregnant and has a tiny bump, Hiccup overjoyed and happily telling Astrid he can't wait to be around during her entire pregnancy unlike when she was pregnant with Dagny. As they watch their little girl dance around New Berk and enjoy the day, Hiccup takes Astrid's hand and tells her how lucky and blessed he feels being there with her and their daughter. They look out across the ocean, remembering the people they've lost, and then look back at Dagny, hoping that she will never go through the same pain they did.
And that would have been the story! I want to thank everyone who was reading and I'm sorry I couldn't finish it. Until next time.