Hip Hop is a common repertoire for idol groups. It allows for a sudden break from plain dance songs and creates a somewhat unique image for the groups. Most idol groups have one or two designated rappers, and with Hip Hop back again on the rise to popularity, it's time to see who is the best rapper among the idol groups.

Most experts agree that out of the rising idol groups, Block B's Zico, BTS' Rap Monster, B.A.P's Yong Guk and B1A4's Baro are four among the best rappers. These rappers were rated on five critierias - rhyme, flow, lyrics, rhythm, and style. The grade for rhyme focused on each rappers' ability to make words come together, while the grade for flow focused on the meter that the rhymes were put together. Lyrics had to do with how unique and creative the lyrics were, while rhythm focused on how the flow was laid out on a beat. Style had to do with whether each rapper had his unique style that distinguished them from each other.

Block B's Zico was given the top grades. He excelled in both rhyme and rhythm, and his flow was said to be the best among fellow rappers. Even when his tone gets higher, he is able to express the lows and highs of his flow. Experts point to "Niliri Mambo" on Block B's first album, Block Buster, saying, "We don't know if he was born with it or if he practiced really hard at it, but Zico has a flow that doesn't waver even in the strongest of beats."

BTS's RapMonster was a close second, whose grade for his rhyme was better than Zico. His rap on "BTS Cypher PT.2:Triptych" from their mini album School Love Affair is a good example of this. Experts commented on this track, saying, "His swagger makes his rhyme interesting, and he doesn't get tied up easily on different styles."

B.A.P's Yong Guk received high praise for his style. His low voice and rapping style is reminiscent of east coast rapper Shyne. His rap on "Bad Man" is a good mix of 'Shyne'-like style and a Korean-oriented flow.

B1A4's Baro received the lowest grades, with experts calling out his plain rhyme and simple rhythm. However, they also expressed that Baro's unique style is noteworthy and that his rapping style is akin to plain speech, which works very well with certain songs, such as "What You Want to Do" or "Gil (Road)". Critics also say that Baro's rap in B1A4's "Lonely" shows that Baro has the potential to be an even better rapper.