The scene before the OP immediately gave away who the antagonist of this case was for me. It wasn't much of a surprise, though, since the return of Gentleman in the previous episode already made it seem likely that this character would make a return as well in this season. If you've watched or played the first Danganronpa, the setting of this case will probably feel very familiar. Based on everything introduced in this episode, this case looks like it's going to be one wild ride and I'm excited to see how Kindaichi tackles this case.