Atreyu is an American metalcore band from Yorba Linda, California, formed in 1998. The band currently consists of clean vocalist Brandon Saller, guitarists Dan Jacobs and Travis Miguel, bassist and unclean vocalist Marc "Porter" McKnight, and drummer Kyle Rosa.

Metalcore is a fusion genre combining elements of extreme metal and hardcore punk, that originated in the late 1980s. Metalcore is noted for its use of breakdowns, which are slow, intense passages conducive to moshing, while other defining instrumentation includes heavy guitar riffs often utilizing percussive pedal tones and double bass drumming. Vocalists in the genre typically perform screaming, more popular bands often combine this with the use of standard singing, usually during the bridge or chorus of a song. However, the death growl is also a popular technique within the genre.