Before I bought this, I heard a lot of complaints about the game being much too easy, even on Hard. Citing issues such as enemy AI lacking aggression, and the assault rifle just killing most enemies with one headshot. Many people said they weren't given many reasons to use abilities or the myriad of options the game provides you, cause just shooting dudes in the head did the trick 90% of the time. So I made an early decision to jump in on Nightmare.
I'm about 7 hours in, playing with M&KB on PC, and I have had to consistently use pretty much every tool I have. It seems the biggest difference between Nightmare and Normal/Hard is that unarmored enemies don't just die instantly from a single AR headshot, which changes the encounters up dramatically. Crowd management becomes an issue, and you if aren't constantly moving around and weaving between enemies, you get pretty much annihilated. You can still take damage, you don't just drop in one or two shots, but you're definitely not tanky.
Another huge change I noticed from the quicklook (which was played on Normal), is enemy AI. They seem to be wildly more aggressively and will bombard an area with grenades if you stay still for longer than 2 seconds, Call of Duty Veteran style. This would be annoying and frustrating, if the game didn't encourage constant movement, but it does.
I've really been reminded of DOOM 2016 with the way the encounters have been going. Constant movement, switching weapons constantly, and very precise & satisfying gunplay. All of this I attribute to the Nightmare difficulty setting. Without it, I imagine I'd be playing it just like Jeff was on the quicklook, just shooting dudes in the head, getting shot up and the health bar barely moving, spending more time driving to an encampment than actually clearing it.
This isn't the first time I've encountered this kind of phenomenon. I've always been an advocate for playing games on their hardest difficulty, because they forceyou to engage with all the mechanics. Granted, there are a myriad of cases where the gameplay and mechanics of a game are simply too shallow, and turning the difficulty up just makes it tedious and is more of a detriment. That is not the case with Rage 2, and I'm having a ton of fun.
I'd like to hear if anyone else is having a similar experience, or can think of another case where turning the difficulty up on a game changed the experience for the better.