Rogue is an often overlooked character in the Marvel universe. Whenever the X-men face some super powerful or difficult to deal with opponent, I always wonder why no-one thinks "Let's just let Rogue deal with it." Whenever I see discussions on what can kill Wolverine or the Juggernaut, she is almost never mentioned despite the fact that she could kill them with a touch.
In all of the continuities that I am aware of (except for the terrifying Escher painting of overlapping timelines that is the cinematic universe) if Rogue kills someone by using her power, then she permanently gains that person's abilities and memories. But is there a limit to this power of hers? Could she absorb Xavier's mind powers, then use those mind powers to immobilize other mutants so that she can absorb their powers as well? Is the limits of her powers ever discussed in the comics or cartoons (I am not terribly interested in the movies)? Could she conceivably absorb Galactus's power, making her the most powerful character in the Marvel universe?