Mystery Machine

Who is that in the Mystery Machine? I saw some kids in the Mystery Machine And I thought it was Scooby and Shaggy Scooby and Shaggy Scooby and Shaggy Scooby and Shaggy Scooby and Shaggy Scooby and Shaggy Scooby and Shaggy Scooby and Shaggy Oh, who's that kid with the scary mask Yeah, who's that kid with the scary mask I thought he was A real monster A real monster A real monster A real monster A real monster A real monster A real monster A real monster