[SPOILER] Which rapper from an idol group impressed the audience on 'Mask King' this week?

SEE ALSO: Adopted daughter's letter leaves Jin Tae Hyun in tears after couple gives up second child plans

The contestant appeared as 'Santa Grandmother' and faced off against 'Nutcracker' in the first round. The two singers performed Sechskies' "Couple" together. Despite the two very different vocal tones, they managed to work together in an amazing fashion and harmonized surprisngly well. Throughout the performance, the panel pointed how unique 'Santa Grandmother's voice is.

Unfortunately for the 'Santa Grandmother', she wasn't able to get past the 'Nutcracker' and lost in the first round. After learning the result, she revealed her true identity and it was none other than LE of EXID! Once the panel and the audience realized who was singing on the stage, they were shocked as they had little idea that LE could sing so well.

Check out her performances on the show!