Sinistar

Few games have made as big of an impression in as little time as Sinistar did on me.  The sound in this game was unparalleled.  All of Sinistar's dialog was great, and his bug nuts crazy roar as he began his relentless pursuit of you was a true horror of the Pizza Man experience.  This is a game that understood (much like X-com) that the imagination is far scarier than what can be depicted.  So Sinistar did the great majority of his smack talking off screen.  Even though the gameplay was kind of pedestrian, this game is a classics classic based on its presentation alone.