The pilot variety show consists of two episodes and brings together a group of individuals whose physical/visual appearances may seem inadequate for the title of a "hero", but who will work hard to prove that anyone can become a hero.
In Hoshi's case, his fellow Seventeen members tried to test whether or not Hoshi was physically "strong enough" to be a hero before his recruitment. However, Hoshi ended up losing in arm wrestling to all members present, including Seungkwan, DK, Vernon, and S.Coups. The superpower they discovered in Hoshi turned out to be none other than keen sight! While rehearsing choreography, Hoshi proved that his keen sight allowed him to tell the slightest differences in angles, as little as 3 degrees.
You can also catch another superpower the show discovered in Hoshi during the cast members' surprise welcoming event, when the idol maintained his smile and fixed his "idol hair" despite having water thrown at him, below.