As Cornelius, Keigo Oyamada has stretched his vision across frenzied indie rock, lush '60s-style pop, psychedelic funk and glitched electronics, all deconstructed and reassembled like a neon cubist-pop sculpture. After a little more than two decades, no one can really imitate his complex cool. Sporting a pair of sunglasses (always), Oyamada recently brought his band from Japan to the Tiny Desk on