His works are known for their “notational overload” and are very difficult to perform. He has been called one of the founding fathers of “New Complexity” in the post-modern musical era. Ferneyhough’s solo piano piece Lemma-Icon-Epigram is scary just to look at. Rhythms that look impossible plus weird tempo markings might scare away a performer. But when played, Ferneyhough’s pieces prove to challenge listeners as well as the performers.