Rookie girl group MAMAMOO finally debuted with the support of Wheesung, K.Will, Bumkey, Rhymer, Jung Joon Young, and CNBLUE's Lee Jong Hyun.

MAMAMOO released debut mini album HELLO and its title song "Mr. Ambiguous" through online music stores.

Popular composer Kim Do Hoon produced the 7-track album with tracks "Mr. Ambiguous," "HELLO," "BATON TOUCH," and other tracks. Gigs, Bumkey, K.Will, and Wheesung feature in tracks.

"Mr. Ambiguous" is composed by Kim Do Hoon, with the lyrics by Gigs member Louie. The song is a retro funky genre with a blues-rock chord progression.

The members of MAMAMOO is a talented girl group who have demonstrated skill in composing and songwriting as well.

WA Entertainment stated: "MAMAMOO's debut album is a very energetic but serious one with MAMAMOO's colors shown through different genres."