NuffCatnip: There are a few portions that are somewhat tough, but the game never came across as very difficult. I think it's pretty fair. I had trouble in the demo of the second game though.
If you elaborate on the parts you mean are too excessive, I could run the game and test it. :)
phaolo: I'm just reporting what some reviewers say.
It seems they lose all their lives at the "Tank boss", which has been buffed too much.
Also, I'm baffled by the forced game restart..
The claims about the difficulty of the FPS games coming out in the last decade or so are, as always, grossly over-exaggerated. Rest assured, I haven't played an FPS in recent history that was harder than the original Doom or Blood. Especially all these new "retro" shooters tend to:
1) Flood the player with ammo. I am drowning in it the entire time, be it Dusk, Hedon, Project Warlock, Amid Evil or pretty much any other "old school" FPS.
2) Have aversion to durable enemies. Any enemies that take a little effort to kill are instantly yelled at as bullet sponges these days for absolutely no reason. The more years go on, the more grateful I am for enemies like the Baron of Hell in Doom.
3) The most recent thing that seems to be clawing its way into FPS games is an allergy to enemies having hitscan attacks. The most recent example would be Hedon. There is even an enemy that uses the same weapon as you, yet for whatever reason, their bullets are not hitscan, while yours are. I also couldn't believe how many people were complaining about like the 2 enemies that have hitscan attacks in Serious Sam 4.
Rest assured. If you played and finished Blood, Doom or Wolf 3D, there is absolutely no reason to ever worry about difficulty in any of the recent FPS games.