Glorious. If Hotline Miami was a Doom game) Well executed. Suggestions: Auto-swap guns when out of ammo; On later stages I would expect stronger monsters who can kill with a few shots, but their projectiles are slower and can be avoided. Some auto-aiming, especially when enemy is near - that is when it's hard to recognize what is going on. Also I was making a voxel-based topdown shooter years back, some thoughts: https://www.quizcanners.com/single-post/2017/12/17/Top-Down-fps-shooting-mechanics
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Will there be an expert mode with very high damage values? (Like in Hotline Miami)