Blood [1997] was so brutal with its hitscan enemies that it accidentally became a proto-tactical shooter.
You must approach hitscans methodically, either by closing the gap and firing both barrels or shooting while strafing sideways in and out of cover.
It is also it is much preferable to just clear rooms with dynamites rather than to take direct gunfights, similar to how CQB is handled IRL.
The pacing of the game is much slower and more methodical than its contemporaries. You will often find yourself playing Blood as if it was Counter-strike in the sense that you are constantly pre-aiming corners and strafing laterally in and out of cover while shooting.