haunting/dark classical

Mozart - Piano Concerto #20 in D minor K.466
Brahms - A German Requiem Op.45
Tchaikovsky - Marche Slave Op.31
Liszt - Totentanz for piano and orchestra
Prokofiev - Scythian Suite Op.20
Mahler - Symphony #9
Shostakovich - String Quartet #8 Op.110

A good sampler. All of the compositions are "standard repertoire" and recordings are readily available.

Cheers.