Sif and Volstaag spend their time en route to meeting Thor, by telling each other stories from Thor's past that highlight the treachery of Loki.
This is a 'point-one' issue, which means that it would be a good jumping on point for new readers. Sadly, it is just a number of mini-stories one after the other that are 'told' by the two protagonists to each other in the most mundane "do-you-remember-the-time-when" fashion. These stories project Thor as a gullible person, the major motivation behind his actions being his scheming brother who consistently manipulates Thor and strokes his ego. A point-one issue should not give such an image of an iconic character to new readers. It should be informative without being expository, and comprehensible without being monotonous. The Mighty Thor 12.1 is an epic fail by these standards. The regular readers can easily skip this one. However, one of the stories that shows Thor masquerading as a bride is taken from actual Norse mythology, and is quite entertaining. It would have been a good one-shot on its own merit.
Guest penciller Barry Kitson is the saving grace of this issue. We get page after page of unique character designs, be them huge rat-terriers, frost giants, hunting scenes, or pictures of Volstaag's youth. The backgrounds too are rich, with every detail begging to be looked at and explored. It is simply amazing how consistently good the art has been on this title, that too in inverse proportions to the quality of the storytelling.
It is strange that it took two artists to draw such a generic cover. This is a 'routine' Thor cover that we have seen so many times, albeit better drawn. The background is a just a blue sky/thunder that doesn't help add to its appeal. This might have been approved for a point-one issue, but this is as boring as the story it hosts.
Marvel's flagship Thor title has been consistently sinking, largely owing to Matt Fraction's uninspired stories. This issue is no exception.