“Now that I’ve played Duke Nukem 3D and Shadow Warrior, there’s only one of the Big Three build engine games left to try.”
“Hmm… I’ve finished D3D and SW on hard, so I’d better put this on the ‘Well Done’ difficulty.”
TEN MINUTES LATER…

Blood is kicking my ass.
The difficulties were made with co-op in mind. If you’re an FPS veteran, play it on the middle skill. If you’re a little less sure, play it on one of the two skills at the top. No shame. Blood on medium and higher is brutally hard, but it’s also one of the greatest FPS games ever made.
Everything about it is masterfully done. There’s so many barely-noticeable bits of ‘game feel’ that make the combat fluid and satisfying. Highly recommended.