Here's what kind of dragon's the teens are:
Hiccup: Night Fury
Astrid: Deadly Nadder
Fishlegs: Gronckle
Snotlout: Monsterous Nightmare
Twins: one Zippleback
I know I'm not original but I think they are the dragons who they bonded with in the movies.
A few months later during a raid Valka got taken by a dragon while the children were seen to be picked up by a mysterious lady who is later said to have been Loki. The God had been bored again and was going back to Berk to check on the little hybrids he created. He compulsively decided to take them after he watched one of the mothers go off with a dragon. If a dragon could take someone from Berk he had every right to take the kids he used his magic on, at least in his mind.
Loki made sure no one saw him when he came into Asgard with an armful of babies. Of course he could never do stuff behind Thor's back, sometimes he swore the thunder god saw more then Odin. "Brother what do you need with those mortal babies?" he asked as Loki put them on the giant bed in the middle of the room. Most of them were asleep except for the son of Valka who had a fresh cut on his chin. Loki tisked and picked the crying boy up again shaking him lightly to calm him down. "They were left behind by their parents and I took pity on them" he lied smoothly dapping at the cut with a cloth murmuring to him to stop crying.
Thor was not sure that Loki really felt sorry for the young Vikings but he seemed to care enough to take care of the cut on Hiccup. "Do they have names already?" the lightning God asked grabbing a blanket to tuck in the children on the bed. "Of course they do they're too old not to have names" Loki rolled his eyes laying Hiccup with the rest. Thor hadn't moved away from the bed still looking at the sleeping children. By the look on his face Loki knew Thor would adore them, he sighed running a hand over his face. "The largest child with blond hair is Fishlegs, the twins are Ruffnut and Tuffnut, the dark haired boy is Snotlout, hatchet girl is Astrid and this little fishbone is Hiccup" once he was done naming them all he ushered Thor out of the bedroom.
"You must swear to leave father out of this. If he finds out about them I will not have mercy" Loki told Thor icily making Thor hold up his hands in surrender. "I promise not to mention them to father. But I want to take care of them too" the mischievous God thought about it for a moment considering the perks of having Thor taking care of them too. "Fine." he said shortly further pushing the other out. "But for now you leave. You may come by again tomorrow" he closed the door and rubbed his brow muttering softly.
As the years went on the kids grew up and found their own connection in Asgard. Odin had known they were there the moment Loki had set foot in Asgard again. Heimdall had told him about them, but something had the alfather hold back from getting them back to where they belonged. Maybe because he saw a new tenderness in Loki. Or maybe because he knew that these children would have no place among their people as they were.
The first few years only Loki and Thor raised them. But after they turned five each child picked their own Asgardian to look up to. The twins stuck with Loki because of all the misschief and magic. Snotlout tuck to Thor because of his power and strength. Astrid looked up to Sif a female warrior who was loyal but kind. Fishlegs had taken to Frigga, she was kind and knowlegable which appealed to the shy boy. Hiccup had his eyes set on Heimdall who at first didn't want anything to do with him. But once he noticed others had taken after the children he allowed Hiccup with him for his love and curiousity of the world.
A loud blast woke Loki up early in the morning and he groaned grumbling lowly. He got up rather quickly putting on some robes and went out to look for the source, or rather sources, of the blast and tell them that it was too early to blow something up. He walked past the library where Frigga was going through some books on history with Fishlegs. Neither looked up as he passed too focused on the books. There was smoke coming from the twins' room. Steeling himself to rant Loki turned in the doorway to find the whole room covered in black ashes. "Have I not told you two that if you blow up your own room, you do it after most of the palace is awake and that blowing up your own stuff is not how you create the response you want" Now he spots movement in the room as a zippleback slowly shrinks back into two separate people.
"We just misjudged how unstable this potion was" Ruffnut mumbles dusting the ashes off of herself. "Maybe we added to much bear hairs" Tuffnut puts in looking for the remains of the bottle. "Three bear hairs no more no less. I'd write it down but you two don't read" the twins groaned at the mention of reading. "I expect you to clean up your room and be in study after breakfast" with that Loki walked out of their room and went back to his preparing for an other lesson.
Snotlout was really struggling taking the blows from his partner's axe just barely. With Thor cheering him on he felt more confident but his partner was being directed by Lady Sif which made his confidence go down again. "Go easy on me babe and I will go easy on you later" he said to his partner who let out a low scoff and knocked his feet out from under him in his short distracted moment. "First off I'm not your babe and second, I'm not interested" she turned swinging her axe over her shoulder walking over to her mentor. "Good job Astrid, you won the fight but your footwork is still a bit off sometimes" Sif told her hand on her free shoulder in a kind gesture.
"Do not worry Snotlout, winning women over might seem hard but it will get easier with time" Thor said good heartedly patting Snotlout on his back as he got up. "Things are always going easy for Snotlout" he hit his own chest with his fist grinning at Astrid who rolled her eyes leaving with Sif. "Let's practice some more young friend" Thor said to the nightmare hybrid who turned getting ready for his next lesson.
Between a pile of books sat a young man with auburn hair his nose buried in a book about the history of Berk written by Jord. Not too far away from him stood Heimdall looking out into space guarding Asgard as he did everyday. The only thing that changed in the guard's life was the young viking boy who had a curiosity for the world and a lust for knowledge. Seeing how every other god had taken in one of the mortals Heimdall felt he could too with this one. "Berk is still one of the few villages on Midgard that is battling dragons rather then living with them" Hiccup muttered his eyes gliding over the last passage of the book having caught up to the present of his old home.
"Can you see the village now?" the young man asked grabbing a new book, this one being about plants on earth, while Heimdall hummed shifting his gaze just a bit. "I can see it. There had just been a dragon raid not much was taken but only because there wasn't much to take." the guard's voice was grim as he shifted his gaze again. "There are ships going to the dragon's nest. I'm afraid it won't end well for the vikings" with those words Heimdall looked away from the Barbaric Archipelago to the heir of Berk who seemed to be staring at the page but not taking in the words.
"It is time for lunch young one. Relax your eyes and go mingle with your kind, I will keep my eyes out on your village" Hiccup put away the book with a tiny smile directed to his mentor nodding in appreciation as he got up. "If you're lucky you might get there in time to eat with Astrid" Heimdall called after him making the young boy flush red.
When he entered the dinner hall Astrid was munching on a chicken leg she seemed relaxed enough to let some of her Nadder features melt in he noted as he saw her spiked tail swish back and forth. He sat down next to her grabbing some smoked salmon from the platter letting himself relax enough to bring out his own dragon features.
"Usually you eat lunch later so either something happened or you listened to Heimdall for once" she remarked still staring out in front of her. It startled Hiccup a bit how well she seemed to know him "Well you know, sometimes it's good to listen to your mentor besides I think I will go on a flight a bit later so I need to get some food inside. Wouldn't want to drop into the sea like last time" he laughed awkwardly taking a bite from his salmon to keep himself from talking even more.
"I could come with you if you don't mind" this time she did look at him a soft smile on her lips. Hiccup almost chocked on his fish cursing his teenage hormones as he coughed his face red, not just from almost chocking, Astrid is patting his back though she seemed more amused then concerned. "I will take it as a yes" she tells him once he stopped coughing. "Oh, yeah totally, I'd love it if you came along, I mean your company is always nice and flying alone is only nice when I feel like it and I don't feel like it right now so..."
Now she's chuckling and Hiccup really wants to sink through the floor. "You're lucky I have a thing from rambling Night Furies." is what Astrid says as she gets up from the table having finished her lunch. "See you in ten minuets" she has turned her back to him swaying her hips as she leaves. "I guess I'm really lucky then..." he mutters stuffing his face with fish so he can fly with her as soon as possible.