The above video for your enjoyment features Bill Gates, dressed in a black trench coat and carrying a shotgun, inside of the Doom game. Apparently it was a promotional type clip used to introduce Windows 95 and DirectX at the Microsoft Judgement Day event in 1995.
Basically Bill is in the game and wants to share his feelings about how Windows 95 and DirectX is ideal for playing PC games. DOS is too hard to use to play the games. At one point a Doom character shows up and gets blown off the screen(Not very convincingly) with Bill saying “Don’t interrupt me”.