User blog comment:GobletPotion/The future of the Dragons franchise/@comment-27609869-20160203011418

I doubt any major deaths will occur. HTTYD 2 was supposed to be darkest chapter of the triology. It's still possible a character might die "off-screen" since HTTYD 3 is going to jump back and forth in time. I also suspect a new war to unravel between humans and dragons that could eventuelly result in the dragons taking off.

I hear Toothless is going to be the front and center of the third movie, and that Astrid is quite a bit in it, too. Drago is also confirmed to be returning as well as Valka. We may get a confrontation scene between Valka and Drago. That would be pretty interesting, imo.

The only "on-screen" wedding I see occuring is the one between Hiccup and Astrid. If they include it as a part of the movie, it will be short but flashy. If they decide for a wedding short/special, it will be less traditional and possibly revolve around a larger story-arc.

I don't see Ruffnut getting married to either Fishlegs or Snotlout. As for Heather, I very much doubt she will be appear in the movie. Dean DeBlois finished writing the script last summer. He had no contact with the writers of Race to the Edge over it. Since Heather is not Dean's character, I doubt he will attempt to make room for her. If she appears, it would be a visual apperance in the background, a small blink-and-you-will-miss-it cameo. I also don't think he will be introducing any new main characters. Most of the movie will revolve around Hiccup's coming-of-age, him growing independent from Toothless and vice versa. There is also a big backstory dedicated to both Toothless and Drago. And we know for fact Valka and Astrid have significant parts in the overall arc. With the rest of the supporting cast included, t here is simply not enough time for anyone else.

I think the next season promises more Gobber and how he met Grump. We will be seeing a lot of Heather, too. She has a dragon-lence that I'm sure will come into play. There will also be a fair amount of Dagur. I heard rumours of a redemption story for him. It's very likely he will end up sacrificing himself for a good cause, possibly his sister. Dagur is said to have some very interesting interactions with Hicup and the gang in the upcoming season.

Hiccup and Astrid will most likely not get together until the last season. I think a danger evoked kiss is possible but since the writers have been so cautious about this relationship in the past, they might just settle for some flirty moments in the background. Although, I have read there are some big Hiccup and Astrid episodes coming up. I guess we will just have to wait and see.

I think the Dragon Eye as well as Dragon's Edge itself are going end up being destroyed. The writers have definitely been hinting at it.