Counter to the epic symbiot
Now my tactic to beating the symbiot is simple, it requires a damage immunity champ, like luke cage and also magik. For me it is magik. Magik's limbo ability to you that any damage you take during that time is reversed. So when the timer goes off you take the damage but if you have limbo on as well then you can reverse it all. BUT it is a matter of how much health you have.