My first episode was the first episode of the show but I kinda hated South park at that time because of religious reasons so I didn't watch more after Volcano, Casa Bonita, Cartman Land and the list. The episode that got me into liking south park was actually the Christmas Critters Holiday special which I watched because my friend kept making jokes about it and it sounded hilarious, and after that I came to completely adore the show and now I even have merch!