Personality Out of his siblings, Cory is depicted as being the mindless child, with intelligence and outbursts akin to Mario. Due to his erratic nature, he has been a target of minor manipulation from his brother Zack. Cory Katphish is a major character in the SMG4 series. He is one of Karen's three children and the triplet-brother of Zack and Katie. Unlike his siblings, he usually doesn't speak coherently and instead usually only quotes memes or makes random noises to communicate although he does have rare instances of talking coherently.