Deathcore, a musical genre that combines elements of death metal and metalcore, has evolved and expanded since its emergence in the early to mid-2000s. The genre is characterized by its aggressive and intense sound, featuring heavy guitar riffs, blast beats, breakdowns, and harsh vocals ranging from deep growls to high-pitched screams. While its predecessors in the 1990s laid the foundation, deathcore came into its own in the 2000s with bands like Despised Icon, Through the Eyes of the Dead, and Rings of Saturn, who blended death metal's complexity and speed with metalcore's breakdowns and lyrical themes. The history of deathcore can be divided into three main periods: predecessors in the 1990s, origins in the early to mid-2000s, and expansion in the late 2000s and beyond. During the predecessor era, bands like Dying Fetus and Hate Eternal incorporated elements of death metal and metalcore, paving the way for the genre's development. The origin period saw the emergence of bands that fully embraced the deathcore sound, with Despised Icon often credited as one of the first true deathcore bands. This period also witnessed the rise of other influential acts like Through the Eyes of the Dead and Rings of Saturn, who helped solidify the genre's identity. The expansion era of deathcore began in the late 2000s and continued into the 2010s, with the genre gaining wider recognition and a growing fan base. During this time, deathcore bands started experimenting with new sounds and fusions, incorporating elements from other genres such as black metal, symphonic metal, and even electronic music. This evolution led to the creation of subgenres like "deathcore-influenced metalcore" and "deathcore-influenced death metal." Despite criticism from some quarters, deathcore has firmly established itself within the heavy metal landscape, with a dedicated fan base and a continuous stream of new bands emerging to push the boundaries of the genre.