Dr. Najib is somehow able to produce three concrete replicas of himself, the professor, and Scooby in a manner of minutes, then carry said replicas to various places by himself. Even if he somehow used a cart to lug the statues around, there’s no explaining how he was able to make them accurate down to the last detail so quickly.
From TV Tropes: Scooby-Doo, Where Are You! S1E12 “Scooby-Doo and a Mummy, Too”
