Silver Surfer is re-controlled by Galactus, and as of that result he invades Ysmault(sensing the power core and lanterns would feed Galactus greatly). Atrocitus confronts the Silver Surfer. Atrocitus is of course enraged(even more) at the fact that he is being threatened by this unknown being, after overcoming the near destruction of his planet and the universe by Parallax and Anti-Monitor. He then strikes Surfer first and they engages in a battle.
Battle takes place on Ysmault. No BFR. To the death. No aid.