Last night, I opted to try my luck at championing DOOM3 on the hardest difficulty: Nightmare. Having breezed through the game on Veteran, I figured it only fair that I try for victory on the now-unlocked and most difficult setting.
Nightmare is distinct from the other levels of difficulty in that there are no medical kits (though wall-mounted emergency units are still in effect), ammunition is more abundant (unnecessarily, in my estimation — there was far too much on Veteran… and now there’s even more), and — here’s the real kicker — the health of your character is in constant flux. Any health procured is temporary, dropping to a maximum of twenty-five percent at a rate of (approximately) one point per second, with a condescending demonic voice admonishing you for being “obsolete”. Additionally, you start the game with the Soul Cube, something you wouldn’t normally obtain until two-thirds of the way through the game. Though the Soul Cube grossly unbalanced the final third of DOOM3 on Veteran in favour of the player, it has thus far proven itself invaluable, and seems essential for making completion of the game on Nightmare feasible.
I’m having a blast, though I can’t say the same for my enemies: I’ve played for only a handful of hours and I’m already in the Delta Labs, having torn additional orifices into every creature encountered thus far. To say that the ever-diminishing health of your character is motivation to move quickly would be an understatement of gross proportion: when you’ve only got the health temporarily, and the munitions to really kick some ass, you move, and you move fast, making every second count.