I've been thinking about it a while ago.

Dreams vary greatly.
Some dreams show common human fears (like killing, undead, and gore)

and thus they are considered a nightmares. Funny thing, they are not.

These are just dreams of undead/violence/death.


What qualifies as a nightmare is a dream, where *YOUR PERSONAL* fear

comes to life. Something that specifically terrifies you.

Something you dont want to happen.