There are brutes, electrified guys, ninjas. All enemies who you cannot hit directly (usually). That's not considering stun baton and shield guys.
It does have an impact on the combat, at least it did for me. It took some of the 'flow' out of 'freeflow', because it's quite common in combat scenarios (particularly in the late game) that they are more enemies you can't attack normally than there are enemies you can. So when you have to leap over a stun baton person, stun-jump-jump shield people, attack ninjas and be aware that they can dodge, hit electrified guys with a projectile and stun and beatdown brutes, watching out for tackles that could be coming from off-screen, the combat can become very 'dense'.
Even when I'm doing it well it isn't with as much style as in City. In that game the challenge wasn't so much from the enemies themselves, but a personal challenge with regards to how efficiently you could dispatch your enemies. In this I found myself really having to strategically target specific opponents, and that was usually something reserved for Predator sections. As such I found that I enjoyed the dual-play sequences, where you could be stylish and playful, more fun that the harder combat sequences in Arkham Knight.
Actually, I think it's interesting to dissect the Predator mode here too.
While I never felt they were that 'hard' in the other games, I felt way more...passive here, I guess. I felt like you could accomplish A LOT just sitting on a perch taking everyone out. The Disruptor has always been powerful, but it seems to be even moreso here--and serves as a hard counter to almost everything new they added. Like Medics, cool addition! They'll go around and pick people up, so you want to prioritize them. But I don't think I have a single instance where I actually felt their impact, as the disruptor serves to essentially be a long ranged takedown as they will incapacitate themselves. So will the mine users. So will people deploying a sentry. It's not just threat removal such as not having a sentry or mine to deal with, it straight up takes out whoever uses them in the first place. On top of that, you have complete control with the voice synth to specifically pick your targets and send them anywhere to take them down which is better than the sonic batarang ever was. On top of THAT, Fear Takedowns, as cool as they look, are...pretty damn OP as they let you clear a whole crowd that goes to check on a body(like the aftermath of a medic getting shocked).
I think it would have worked out better if the disruptor didn't fully shut down medic packs. Like maybe the first one would do that, but someone else would take over and pick up the additional medpacks and use them, so you'd have to use 3 shots of ammo to take them out of the picture(which is a hefty investment and would actually be a harder choice to make). I like the Boa Drone dudes since that's actual risk reward, get close to hack the code and turn the drone into a potential triple incap. I don't feel there was enough of that, as the current way things work would mean they basically need a massive predator section full of 20+ people, multiple medics, etc. so you can't just immediately take out the unique guys from a perch, and the whole learning aspect would come into play more(like the voice synth not working if you use it a lot, but when this actually kicks in there's generally <3 people left anyway).
I didn't dislike the predator sections really, but I felt less like a predator and more like a wizard having everyone in the room take themselves out.
