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The 'monster rookie' covered the legendary rock band's song "Lonely Night". Before her stage, Son Seung Yeon expressed that she was huge fan of the band, saying, "I want to become the first female vocalist of Boohwal."

She wasn't afraid to tackle one of Boohwal's most vocally exhausting songs, and it seems it impressed Kim Tae Won, who said, "Even Park Wan Kyu can't sing this song in one key. I had a good time listening to the original." Bassist Seo Jae Hyuk also commented that Son Seung Yeon is the vocalist he has in mind if Boohwal ever decided to go for a female singer.

Despite her awesome performance, it was Kim Ba Da (Highlight for Spoiler) who took the final win.