User blog comment:27finnsprincess/The Talk About Marcy and Ice King.../@comment-4887658-20121012123248

I have two ideas-

Marceline is Betty reincarnated, but she became a vampire. (explains young Marcy and older Simon)

At the end of the long preview, Marceline says "Stop acting crazy!" I think it may be possible that she says this and Simon Petrikov gets back his mind, but his body stays the same.

I suppose these could both be in the episode.

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