Today Bethesda allows younger generations to slaughter Nazis, German Shepards (pun intended), and Adolf himself in a glorious celebration of FPS origins.

Fundamentally, the original Wolfenstein 3D can still be held as the standard, if not actually a bit more complicated than the first person shooters of today's world.  While games like Call of Duty and Battlefield shove people down graphically grandiose  hallways, pioneers like Wolfenstein 3D encouraged exploration, discovery and puzzle solving.  

Honestly, Doom was my first experience in the world of the FPS, so Wolfenstein is actually about a generation before I came into my gaming prime, but mere seconds into Wolfenstein and its charm instantly grabs you by the balls.  

You can experience it in its first three chapters right here.  Give it at least 5 minutes of your time, and see how it all began!