Board Thread:Lore Discussion/@comment-11296535-20130914180002/@comment-14027812-20140104194054

Due to their immortality, dragons can resist quite well to the insanity caused by eternal prison. Durnehviir is a likely example, although he did asked to be summoned in Tamriel once more. In addition, i think that the theory of Numinex asking to be killed is quite unlikely, because, as i said, dragons grow accostumed to eternity, and the concept of "time" doesn't have the same connotation for mortals and immortals. The way i see it, it would take far longer for him to become insane, far longer than the lifespan of King Olaf, a human.

So i bet on Blades intervention.