So in today's review of... Hey, that's not the title of this episode! But, of all the shows, if you had to make a decision in who has to join, who would it be? The rules are, one character for one show.
For Arrow, we need the Question. The Question can either be the paranoid detective or the serious badass who takes names Question. Either one would be great!
For Flash, Plastic Man! Great comedy relief who has powers able to defeat a speedster and can add some levity to some future dark scenes. Plus, Cisco needs a friend just like him.
For Legends, Sandman! He can be the Justice Society's answer to Ollie, and also I really like Sandman.
Lastly, Supergirl needs Lobo. You know why.