Over the past several years, acts such as Death Grips, OG Maco, and Antwon have blurred the lines between hip-hop, punk, metal, and hardcore, ushering in a new generation of rappers who grew up going to basement rock shows and playing in bands instead of rhyming in cyphers. The New York trio Ratking, known for its mosh pit-inducing live shows, is of a similar ilk. The trio gained national acclaim with its debut studio album So It Goes, a gritty collage of dark, esoteric samples, pounding backbeats, and aggressive, acrobatic flows. The group reportedly wrote its follow-up project, the 2015 EP 700 Fill, in only a week, releasing it as a free download through BitTorrent instead of selling it on iTunes. On 700 Fill, the group experiments with ambient, melodic production, with Wiki, Ratking’s founder, assuming the foreground with his dexterous rhymes. Ratking opens for indie rock giant Animal Collective at The Fox Theater in Oakland on March 7.