User blog:Winnermillion/Who do you think the 3 extra characters are going to be?

Who do you think the three unidentified characters in Test Subject Arena 2 are going to be? We already know a Mercenary, the Professor, and orange enzyme are confirmed because they were in the preview image, and Blue and Green were already in Test Subject Arena 1, so that leaves us with 3 unknown characters. Place your guesses in the comments!

P.S. Someone, please take the dancing professor from the below gif and crop it. NOW.