If you are talking about BD, the only hero who can successfully bring the dragon down is Gau, Lorraine and Maria has good cc too but need other character's with cc to help out ( If you notice there is another white bar below the dragon's health, when it reaches 0 it will be stunned)

SO technically you still can have 3-4 character with cc all activating at the same time, but it will most likely NOT happened cause majority of raiders uses the "AUTO" function XD

Do correct me if I am wrong though.