Beyond Castle Wolfenstein DOS

Beyond Castle Wolfenstein is a 1984 computer game by Muse Software. It is the sequel to Castle Wolfenstein, a prototypical stealth game. Both games were the only World War II era games that were First-person shooter. Unlike the original game, Beyond Castle Wolfenstein was originally developed simultaneously for both the Apple II and the Commodore 64, but was quickly ported to MS-DOS and the Atari 8-bit.

- Wikipedia