According to the Marvel Comics, the story line of Ragnarok, which is also the title of the third installment of the Thor film series, Asgard is completely destroyed and everyone dies including Thor and Loki. It’s more or less like the Judgement Day for Asgard.
The big question is “Will Marvel Studios adapt to the existing story-line of Ragnarok from the comics or will there be an alternate ending for the Thor series?” Well, as much as the idea of bad guys getting killed by the hero sounds awesome, Marvel fans might just be reluctant to the idea of watching their favorite villain Loki get killed. Yes, that’s a fate we do NOT want for Loki.
But it all depends on whether Marvel Studios follows the comic script. Let’s hope not! What will be more interesting to watch is what could be the ending of Thor 3 : Ragnarok.