#maybe she has a nightmare and the present and past blur together and she doesnt know if its a memory and she shakes anne and is like:

[theskyexists]

Also man...they dropped the ball so bad on not making Marcy BE THERE for doing all those horrible things..lucid but helpless.SHE COULD HAVE GAINED SO MUCH MORE TRAUMA!!! Almost stabbing Anne WITH HER OWN HANDS. almost killing Sasha. Responding in little ways to her friends or when the core reveals things she doesn't want it to.

Alternatively it would have been so cool if Darcy had been an actual corrupted Marcy.

So ok she gets nightmares, flashbacks to things she has no active memory of, which feel like her own but also decidedly not. Sometimes it's what Darcy did to her friends, sometimes it's weird and rarely helpful knowledge that she doesn't know the source of, which is an ironic twist, sometimes its memories of newts thousands years old, conquering and killing and ravaging other worlds. The Core has left its mark, an imprint. she doubts her own responses, thoughts, emotions - scared they're not her own.