I've been wondering if you guys have any experience some truly terrible nightmares.
Difficult because different people consider different things to be nightmare quality. Generally i've had:
. Movement (speed variable) away from non-descript objects which chase (hostile and neutral emotion) and/or teleport within my field of view as i look around.
. Physical combat involving weapons or my body itself against creatures both human shaped and not... as i suffer muscle weakness/paralysis at crucial moments in the fight.
. Flat out LSD style "What the fuck is this shi- BOOOOOOM AHAHAHAhahahahaha" pointless randomness that's actually forgotten
while i am dreaming. Oddly, i remember i've forgotten this.
. Dejavu, and then GRIMDARK happens on that dejavu. Reaching the point in waking hours when said grimdark dejavu hits again... Nothing happens.
. A 'death' sequence where my eyes slowly closed and everything faded/reduced to senseless nothing. ("DID YOU WAKE UP FROM THAT ONE?" ... Duh.
)
Most times with sound, color, and emotion.
Out of all of these, i've never really woken up with a sense of dread or fear; The closest i get to that is with the grimdark dejavu because it feels real and isn't as discreditable as the other things are. Even then it's more anticipation and anxiety of "Will it come true this time?" So, what i do feel is more along the lines of seriousness, general disturbance, and intensity, all depending on the dream involved. I suppose as long as you remember that the dream is just a dream after the fact, it does diminish the effect it has over you; which is why dejavu is so serious, it follows you into real life.
To reitterate, different people consider different things to be nightmare quality.