<Li> James Cromwell as Professor Robert Callaghan, the head of a robotics program at San Fransokyo Institute of Technology who becomes an extremely powerful masked supervillain . According to film merchandising, this supervillain alter ego is named "Yokai". </Li> <Li> Alan Tudyk as Alistair Krei, a pioneer entrepreneur, tech guru, and the CEO of Krei Tech and is always on the hunt for the next big thing . </Li> <Li> Maya Rudolph as Aunt Cass, Hiro and Tadashi's aunt and guardian . </Li> <Li> Stan Lee as Fred's father . Lee's likeness was used for the character . </Li>

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