On October 31, Mamamoo returned to the Immortal Song 2, singing a rendition of Korean trot singer Bae Ho's song "Backwood's Mountain" (두메산골).
Pada 31 Oktober, Mamamoo kembali tampil di Immortal Song 2, dengan membawakan lagu dari penyanyi trot Korea Bae Ho berjudul "Backwood's Mountain" (두메산골).