You may have been looking for one of the DreamTropes about nightmares, such as:

* FlashbackNightmare: A flashback framed as a nightmare.
* GuiltInducedNightmare: Nightmares about past misdeeds.
* IrritationNightmare: A less intense nightmare that's annoying more than scary.
* NightmareSequence: A scene depicting a nightmare.
* NightmareWeaver: Someone who can cause nightmares.
* PastExperienceNightmare (formerly called Bad Dreams)
* PlaguedByNightmares: A person suffers recurring nightmares due to underlying issues.

(Note: this is not an exhaustive list of nightmare tropes. See DreamTropes for the rest.)

If a direct link led you here, please change it to point to the appropriate trope.
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