Not be confused with another invention, Smurf Smasher.
The Smurf Masher is a vehicle created by Gargamel in the cartoon show episode "The Smurfbox Derby" after he had witnessed the Smurfs in their new smurfmobiles. The invention resembles a primitive medieval version of a steamroller, and its purpose is to smash the Smurfs flat. It is powered by a treadmill operated by Bigmouth, who is lured to chasing after a pot of stew.
Gargamel brought the Smurf Masher into operation when the Smurfs decided to have a race from the top of Mount Smurf to determine whose smurfmobile would serve as the standard model for all future models. During the race, Gargamel found his way onto the course and headed straight for the Smurfs in their smurfmobiles, who barely escaped before the Smurf Masher flattened their vehicles. However, when Gargamel got off the Smurf Masher to look for the flattened Smurfs, they had the Smurf Masher go straight after Gargamel, chasing him out of the forest.