With a unique combination of a vocalist and a painter, OLDCODEX takes in rock, loud, and dance music elements into their music while creating visuals mixed with art to please the eyes. Formed in 2009, OLDCODEX's name combines the words "old" and "codex" (an ancient manuscript). For Japanese, rock music is considered borrowed from the West, but OLDCODEX wishes to create their distinctiveness as reflected in their name. They are also known for their aggressive and inspiring live shows where YORKE.'s emotional paintings color the canvas in tune with Ta_2's hard vocals.
OLDCODEX performed theme songs for many anime series including Kuroko's Basketball, Free!, and GODEATER.