Soldier of Fortune is a first-person action shooter title from Raven Software. You play a soldier-for-hire who must travel to some of the world's most dangerous political hotspots in order to carry out your task. Take part in over 30 missions with tasks such as locating nukes on a speeding freight train to searching out an Iraqi oil refinary. You'll be utilizing the world's most lethal weaponry, including a sniper rifle, white phosphorous grenades, and prototype microwave pulse guns. With realistic body damage, interactive 3D environments, and the Quake II engine with new GHOUL technology to back it up Soldier of Fortune is placing you into a realistic world filled with violence.

FlippedOutKyrii says

9/10 - Agree Disagree

Brutal, sadistic and barrels of fun!

It's also among the few multiplayer games I have enjoyed participating in, with a great, lengthy singleplayer campaign on the side.
Even without that, you'll be swimming in guts throughout your entire multiplayer experience for hours on end. If you find a copy, pick it up, you won't regret it :)