Didn't make it to Steam's character limit, so here's a short version.

Nightmare Reaper is simply too much. It's an interesting concept and a unique game that is clearly a fruit of great passion from the developer. Sadly, it's also an FPS that is an ocean wide but an inch deep, with a lot of content, but little to no cohesion.

The randomly generated levels are one of the biggest pain points. There are 3 episodes, 9 unique themes/biomes within those episodes, and then 3 levels per theme. As far as I know, episode 3 has more authored levels, or at least more of them. Everything else is generated randomly, and since level chunks are not shared between themes, the pool for each level group is fairly small. It doesn't take long until you experience heavy repetition, and it's not like quality of said chunks is good to begin with.

There is a lot of fairly dull corridors and bigger cube arenas, which may or may not feature mild verticality. The game's storefront screenshots are fairly representitive here, and also showcase the massive cubed tiles that everything is made out of. IMO one of the greatest elements of "classic 2.5D first person shooters of the 90s" is that usually offered fairly interesting levels to explore and navigate. This element is sorely lacking with Nightmare Reaper's approach.

This could've been not that big of a deal if the game offered little exploration but compensated it with intense arena encounters, which is sadly not the case. Unlike arena focused shooters like Painkiller or Serious Sam, Nightmare Reaper enemies don't really spawn in or come in waves. There are some that hide underground until you approach, as well as enemies who can spawn ads, but aside from that, pretty much everyone is spawned from the start.

This means that even when you get arena like level chunks, it all comes down to opening the door, and then either clearing out most of the arena within first few shots, or channeling all that meat within a tight chokepoint where you can keep pounding enemies until they stop coming. The only exception is the dedicated arena mode. There are 8 arenas that you unlock by exploring the hospital as the game progresses. It's more engaging in terms of combat than the standard levels, but it still gets old rather quick.

One of the big contributing factors to that is how Nightmare Reaper handles weapons. One of the game's selling points is that there are lots of weapons, which is true, and diversity is further enhanced by random stats potentially making the weapon feel and play radically different. However, the game mechanics discourage variety.

After you beat a level, you can only keep a single weapon. There is an unlock to get 2, but you only get it near the end of the game. In theory, I think it was meant to encorage you to try new guns instead of keeping the same ones for too long. In practice, it encouraged me to find one gun that is strong and versatile, because you can't rely on any one level having good and reliable gun drops. Once I did get a second slot, I got more breathing room and could afford to shuffle guns in and out more often, since now I could effectively have a secondary weapon that will cover a specific role and stay with me after the level ends. I think the game would be way more fun if you had more slots to play around with, and maybe a dedicated slot for melee, which is otherwise hard to justify using.

The balance on guns in general goes out of wack pretty fast. Anything can be useful with the right stats, but the spread of shotguns, explosive, and some magic weapons puts them ahead of others, since it makes any modifiers more versatile by extention. A shotgun with shock or explosive ammo will easily cover groups of enemies but also burst down single targets, while getting any of those on a Garand or L96 is almost a placebo. I don't know how difficult the game might get if the RNG screws you, but I haven't died even once and only reached low health 2 or 3 times.

I think this game will appeal to people who just want to boom. You can run around and turn enemies into chunks of meat with coins popping out of them and making that ding ding ding sound when you pick them up and the screen briefly flashes yellow. This part of the game is probably its highest point. You don't have to pay too much attention and get lots of positive feedback from moving around and shooting enemies, so if you enjoy something like Painkiller, Serious Sam, or Vampire Survivors, this might be down your alley.