Noticed something!

3wisellamas:

So, the four places Cuber visits, and three of his four graybles (the first and last were the same one, you owe us Cuber!) were all associated with people in the opening theme:  Ice King, Princess Bubblegum, Marceline, and Finn and Jake.  

In fact, Cuber visits these four places in reverse order to the opening.  

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