Your character has a dream involving a mirror, where they see themselves for the monster or the hero they believe themselves to be. When they gaze into the mirror and remember all that they’ve done, what do they see?
((I'll answer for 3 of my most developed Exiles and Dominion chars, since it's more an in depth question then I'd be able to answer on some <3))
Sindrell Prismawind (aurin): Sindrell's dreams are really distorted visually, due to having no real understanding of seeing visuals in the waking world in the dream world everything is very abstract and if anything more sound and other sense based then visual. But past that fact, in this circumstance she'd likely be unable to fully make out her 'image' as she really doesn't see herself as a hero or a villain. Although if she had to pick one or the other she does think she leans far more towards villain then she ever will hero, since almost everything she does has some sort of ulterior motive to it.
Zetasha Noblinska (mordesh): Zetasha definitely sees herself as a monster. As much as she purposefully pushes people away and holds them off with her coldness, there is a part of her deep inside that longs to be who she used to be, but knows she'll never be again. She's done so many terrible things for the sake of science and knowledge by this point that she can never truly go back. Her tending to the sick in her hospital isn't even for a truly altruistic reason as she typically uses it as a way to further her research in the medal field.
Tanesha Gallows (human): Tan sees herself as a hero, for sure. She protects those who need to be protected, she wouldn't hurt anyone who she feels doesn't deserve it for some wrong they've committed, and she takes in stray animals with no homes all the time. In her eyes how could she be anything but one of the good guys?
Ichiro Soma (cassian): Ichiro has had to do some pretty bad things in his life to get to where he is and to get the money to get by. Because of this he has a very warped view of who he is and definitely would see himself as some sort of monster. And that's before even factoring in his trans-identity issues where he sees himself as a mistake due to being born into a body he didn't feel himself in, so in the dream his 'female' properties will probably be horribly heightened and cause him to feel even worse about himself. If anything I can see this being a recurring type of nightmare for him.
Zimphora Nalkor (dreaken): Zimmy would see herself as a hero, but by being a monster, if that makes any sense. She isn't afraid to take very despicable actions to get something done, but a lot of what she does is often in defense of someone or to help those she likes in some way. So while she'll do terrible things, it's never been for fully evil reasons.
Davian Perronis (cassian): As much as he puffs himself up as something special in the waking world, in the dream world Davian is a much different man. He is very insecure and because of this would likely see himself as a monster. His career path focuses around making money off the oddities of others, and while he's perfectly content doing so and enjoys what he does, that small part of him that's self conscious about that fact would be blown up quite a bit in his dreams, showing him as the selfish user of others he feels he kind of is.