Inte ett riktigt svar eftersom du vill veta om Dexter eller Mandark är den smartare men det var ett avsnitt där Dee Dee blev mer intelligent än Dexter. Detta var Episode "Dexter's Assistant" ( betonar min, jag lägger bara till detta som en svara eftersom det är en av mina favoritavsnitt ):
Dexter puts the brain inside of Dee Dee and she becomes smart. Dexter takes Dee Dee over the the transportation machine again and he gets in. Dee Dee tells Dexter she doesn't think this will work but he ignores her warning, starts the machine and tells her to push the button which she does. However the machine messes up and blows Dexter off from the top and shutting the power down again.
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Later, Dexter is working with fuses and he has a bunch of long flowing hair. Dee Dee tells him what fuses are right and what fuses are wrong but Dexter tells her that he knows what he is doing. Dexter cuts the wron wire and it explodes in his face. Dee Dee tells him that they were all wrong.
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Later, Dexter is at the science fair and shows his great invention. The winner of the science fair gets announced and the winner is said to be Dee Dee who has built a Merry-Go-Round machine...