The first time I ever tested a modern VR headset, I played Doom.
My 2013 PAX West demo came courtesy of Oculus executive Brendan Iribe, who put a duct-taped, unfinished VR headset over my eyes before booting a modified version of Doom 3. Almost instantly, I praised the immersion. I oohed and ahhed at my ability to rapidly turn my head to line up demon-killing buckshot. I appreciated the lighting and perspective tricks used to convey how much chaos was going on all around me. There really was nothing like it at the time.
Oculus continued demonstrating this build of Doom 3 at other events to drum up excitement for its eventual headset, a fact not lost on the folks who happened to own the Doom license. The ensuing legal battle between Bethesda and Oculus has been legendary, but no lawsuit could wipe away that intrinsic link created between Doom and VR by this formative demo.