The game "DOOM" was released in 1993 and is frequently called one of the most significant games in video game history. It popularized the first-person shooter genre of games thanks to its fast pace, aggressive, "push forward" combat system which had never been seen before. DOOM also had a "push forward" ideology on its soundtrack as it attempted to incorporate many of the electronic and alternative art styles that had been developing over the past decades. DOOM accomplished several key things with its music: it used electronic instruments to create a unique "DOOM" sound, it blended the ideas of Avant Garde rock/metal styles with synthetic sounds of electronic music, and made each song on the track reactive to the players actions within the game. While the arcade game Space Invaders accomplished the same reactive soundtrack in 1978, DOOM represents an important milestone in the history of electronic music as it implemented techniques used by preceding games while pushing the hardware and software of the time to create music that represents a culmination of the technological and cultural innovations of electronic music. One of its most popular tracks E1M1, also known as "At Doom's Gate", is an example how DOOM was capable of creating iconic music that literally pushed the electronic genre forward despite the technological limitations of the time.