The first in a set of three pieces by this composer opens with an E-flat minor theme over triplet arpeggios, followed by a restatement in the parallel major. Extremely slow interpretations of the first movement of a late (10[1])piano sonata by this composer were popularized by Sviatoslav Richter, who switched from Bösendorfer to Steinway to record a fantasy by this composer that opens with (-5[1])thundering C major chords in a “long, short-short” rhythm. Brahms edited a set of “three piano pieces” by this composer initially intended to be a third set of four impromptus. This composer declared “the devil may play it” in reference to his challenging Wanderer Fantasy. (10[2])For 10 points, name this German composer whose hundreds of Lieder include settings of Goethe in Gretchen at the Spinning Wheel (-5[1])and Der Erlkönig. (0[1])■END■ (0[1])