It's her means to traveling and escaping. Usually dissipating into shadows, black fog or whatever she prefers.
She is able to change her appearance. Depending on the realm she is in OR/AND on the person who is seeing her, she is able to appear young or old.
Her eyes rarely glow, but when it happens her intended targets can be paralyzed with fear. It is often describe that there are demonic voices whispering and strange figments appearing from the edge of their vision. Even during their slumber, victims have constant nightmares and become sleep-deprived which can cause paranoia, irritability and general tiredness.
She can cause images to frighten others. Because she feeds on fear and doubts, she targets those who are stranded in isolation and makes delusions for them.
Summoning Nightmare creatures
As a half goddess of nightmares and darkness, she is able to twist reality and materialize her opponents greatest fear
. Her common summons consist of closets monsters, shadowed hands that grab ahold of the victim, the darkness and occasionally a horrifying boogeyman.
(Based on children's nightmares and ghost stories)
The nightmares can terrify opponents enough to die from fright or do harmful actions that victims would normally wouldn't do. And on some occasions, the nightmares can push her opponents into insanity.
As long as there are nightmares...she will continue to exist.
((~~P.S. If you wish to know more about the user and not Lily...I'm afraid you'll just have to find out ~~))