Mmmm after reading both points I can see why many people would be led to believe the Bench dragon is Nidhogg, but Alberel's post does open some doors. SE tells better stories than that. A plot where "We are the good guys, that dragon is bad so we should kill it." sounds to plain for SE. I think there is more than meets the eye with both of these dragons, and we may see a big plot twist. I also want to point out the white dragon is on the cover of the box for the game itself, therefore its more than just promotional flare. The bench dragon has only been seen in the bench so far. I'm not saying the bench dragon is or is not Nidhogg, but that the White Dragon does have significance.