I think you'll find that he uses Difficulty = Hardest and 20k, 70k, 70k for the extra lives settings as these are the TG settings for marathon recordings of Galaga. This is also one of the few games on Marp where you are allowed to use 2 credits, so that you can play player 2 to make the final score easier to determine as it shows additional millions and 10s of millions etc digits. You do need to not play player 1's game obviously, although it seems to be acceptable to quickly get rid of player 1's ships by capturing and deliberately destroying them so you don't have to worry about player swapping interrupting your game-play later in the game should you lose both of your Player 2 ships in short succession. This is not officially or specifically noted in the rules for this game... maybe it should be officially noted that this is acceptable as long as it's clearly a case of getting rid of all of the Player 1 ships at the very start of the game?