I don't know, but this doesn't feel like my cup of tea. It feels like it was well made, but there is too many elements that turn me off. These are:

1. Hunting for secret buttons that must be shot, and you never know when you've found them all. I found three such secret buttons, and nothing seemed to happen when I shot the third, though that might be because there was more than three, but the game did a terrible time telegraphing that point (ie a popup saying, 3 more secret buttons to go)

2. The guns felt severely underpowered. The grenade launcher and laser gun in particular, so I ended up using the shotgun the majority of the run. The grenade launcher especially was difficult to use as the physics on the grenade was very different from most grenade launchers... either you have cod grenades that explode reliably on contact, or you have quake style bouncy grenades that are timed, but these ones felt somewhere between the two extremes and I just didn't enjoy using it.

3. Blowing up coffins to get resources, fine. Blowing up a coffin to get a suicide guy appear, blow up and take out 60% of my health before I have a chance to react, not cool.

4. Since weapons felt super weak, all the enemeis were hard to keep at range and without a melee weapon, and even the shotgun feeling unreliable, I was constantly losing health, that I didn't feel I should be losing.

5. Sensitivity is super weird. It starts at 1.5x, and I had to bump it up to 3.1x for it to be usable. Also, the vertical is much less sensitive than the horizontal, so I felt the horizontal was over-sensitive, and the vertical just right. Most games lets you change both of them individually.

6. Game starts out in a window of 1024x768 or something, yet in the options it has fullscreen ticked. And when i change the resolution to 1920x1080p, it goes full screen with no option to go back to being windowed. Very strange.

7. No FOV slider that I could see.

8. Game felt way too dark in places and without flares or a flashlight, it just didn't work for me. Yeah, Quake 1 was dark too... but I played that one 20 years ago when my eyesight was better.

9. Really good soundtrack though. Better than most FPSes on the market. If I had the option to buy the soundtrack I'd probably support you there. But the game, doesn't play that well right now.

10. Felt I had to quicksave far too often. Suicide guys just popping in in tight situations with no maneuver room and no effective weapon to take them out, meant I was saving every 2 minutes or less. And in most FPSes I play, even on the hardest settings, I generally only safe 10-15 minutes apart. So, I certainly felt that it was unfairly difficult in this one.

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If you end up updating the demo with fixes to the above, I might give it another go, but otherwise its a hard pass for me.