It's Beta. He is wearing that for fashion reasons and if you listen closely you can hear him singing his part.

it is b:eta, you can tell by the height and the dance style and you can hear him singing live especially when he's moving around a lot his voice sounds jumpy, it's like when a member of exid had to get her tooth out her face was swollen so she wore a black cloth over half her face

Does beta have the swine flu or something?

Fashion happened to beta that's why he's wearing the mask ! -________- you people I swear

so..why is beta wearing a mask??

i seriously regret not getting there cd

I love seeing B:eta's gorgeous face♥ Why he gotta cover it ._.

Me encanta esta canción xD

What happened to the B: eta? I think he did some surgery. I think he had surgery on nose. If he did some surgery or is ill, hope he recovers soon. I love his mouth, and the mask prevents to see her. AlphaBAT are amazing

I kinda think it's Beta because his dance style seems the same. Plus, I don't think they would dress someone who isn't actually from the group with the group clothes (similar with some of Shinee's everybody performances, the dancer who was performing because of Onew's injury was wearing all black), it doesn't look right to me. I think something happened to his face =/ but I can be wrong, of course xD

honestly that doesn't look like B;eta at all... why is he wearing that mask (even tho it's totally amajjing!! )..??

Did something happen to beta ??!?!??!?!?!?!?!

what happend to B:eta ? why he Wearing a mask ?

Why the mask?! Is it really him?

칼군무대박..... 춤만은 제2의인피니트다

epsilon

don't cover your pretty face , Beta

why does beta wear the mask something must of happened to him , cause i use to identify him was his puffy eyes this person doesnt have puffy eyes, plus you cant sing with a mask and make it clear and perfect.

the vibe of the song is really nice but the chorus lacks power. Their outfits and voices tho have much potential: some are cute, some are more classy so I think they'd be lovely and interesitng to watch on their own variety show. They seem to be able to do many different styles of music because all of their voices are rlly diff so I'm expecting more from these rookies with potential