Cole- he gets nightmares from the day his mom died
Zane- the many near-death experiences he had, and the things he did while corrupted in the Never Realm
Jay- being tortured by Nadakhan, and Nya dying in the alternate timeline
Kai- the day his parents went missing (until they were reunited)
Now, its Skylor being poisoned, but dying instead of recovering, and Nya dying (usually related to the alternate timeline)Nya- Dying in the alternate timeline
Lloyd- his father coming back and killing everyone
PIXAL- the many times she thought Zane was dead
Skylor- she becomes evil like her dad and kills everyone, and the time garmadon's powers poisoned her