The Secret of Nightmares is an Imaginative Secret, and like the Secret of Dreams, exists outside the realms of reality. It exists merely within the dreams of others and can only appear to those who have seen a Secret. When one is having a Nightmare, the Secret of Nightmares can appear before them.
Nightmares is displayed to have a joyful personality and bubbly at that. Kind and happy, Nightmares is a 'cursed' fellow, in the fact he brings misery and suffering in the dream worlds. He also desires to find a way to free himself from the Realm of Dreams in order to become a real Secret alongside Dreams.
Nightmares is somewhat the opposite of Dreams' attitude toward going to the 'real' realm. Being able to live in nightmares is something it is fine with. But when given the opportunity to explore another place it has yet to actually visit, unlike Dreams, Nightmares isn't really too prospective about the idea, instead thinking about the whole idea before actually deciding.
- Nightmare Embodiment
- Psychokinesis Tier IV
- Emotional Vampirism
- Psychic Vampirism
There are a few rules for Imaginative Secrets, and then specific ones for Secrets within dreams, these are specific to Nightmares in order to come across him:
- Must be asleep
- Must be having a nightmare
- Must know of Secrets existing
- Must feel fear