Is this a quest that people are talking about? How do you view the quests because I don't have anything to indicate a quest.
It looks like what you need to do is use the steroid effect (the flexing arm) and have a total of at least 10 damage added to your card. For instance, if Rebel has steroids 5, you have to put rebel on the field, then fuse two pairs of cards so that the steroid effect occurs twice, for a total of 10 damage added to Rebel.