In this video, Jack and Gav tell us how to do the Vidmaster Challenge in Annual Halo 3 achievement. First, start at the mission start point and change the difficult to legendary. Turn on the iron skull, then get four other people to play with. Now, continue to play the game and go up on the platform. Continue to go around shooting things, then come out the doors from the building and go left to find four ghosts that you can use to finish the game after this. Take it slow after this, then you will be able to finish the challenge!