"The Smurfs Springtime Special" is the debut of Gargamel's evil godfather Balthazar who is a creation of Studio Peyo for the cartoon series. He will make his episodic debut in Season 2's "Papa's Wedding Day."
The so-called "magical" weapon that Balthazar used against the Smurfs is called a harquebus, a matchlock gun invented in the 15th century which was portable but heavy and was usually fired from a support.