While Doom and Duke Nukem 3d certainly were gory, the graphics limited the shock value.
How ever Soldier of Fortune was the first game that truly brought over the top violence to the PC. Not only did you shoot humans and not Desmond or aliens but the gratuitous and highly detailed violence was against humans.
A shotgun blast to the stomach ripped it open and guts spilled out. If you shot the enemy with automatic guns they would continue to do a shaky dance as long as you pumped bullets into the long dead enemy.
Naturally this lead to controversy, exactly why I personally don't know. This type of violence had been common in movies for dacades by this point.
But SOF 1 & 2 were old games and unless you happened to have the CDs you wouldn't get them.
But now they are available again thanks to GOG
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