One Nation Underground is the third studio album by the Latin metal band Ill Niño and stands as their final release under the Roadrunner Records label. Upon its debut, the album reached No. 101 on the Billboard Top 200, selling nearly 11,000 copies in its first week. Despite this initial push, its total sales of approximately 210,000 were significantly lower than the near-Gold success of their previous album, Confession. This record also marks the last appearance of guitarist Jardel Paisante with the band. The track "Turns to Gray" features guest vocals from Hatebreed frontman Jamey Jasta, offering a notable highlight amidst the album's heavy, percussive sound.