In the underground lab, Dr. Su offers to surgically remove the false memories he implanted in John's brain. He drills a half-inch hole in the right side of John's forehead, which leaves the right side of his face covered in flowing blood. John can't stand the pain, breaks free, and he goes on a rampage throughout the underground bunker, killing every UniSol in his path. As he fights his way through the bunker, the bleeding hole in John's head switches from the right side of his forehead to the left side, then back to the right side again. Also, in the last scene (an unspecified amount of time after the bunker brawl), John has no scar on his forehead at all.
Although Jean-Claude Van Damme and Dolph Lundgren share top billing, they have no scenes together in the film.