pretty simple and fun game. however, the art style did not match each other, from the zombie fighting and the other one. Particle from the gun also do not match the art style, so I think it will be so much better if you match it.
I think the other dimension, the one you become the pixel art thing (I dont know what it called xD), is already polished enough, maybe some variation in the location / button for interact (Q-E-Q-E) will make it better.
But in the real dimension (where it got zombie), it's nearly done but lack of polishing in details. I got no problem in zombie spawning anywhere even if it's in the player blind spot. However, you still need zombie location indicator like the zombie aaargh sound, or maybe zombie footstep so player can know where is the zombie without looking for it. Hit sound also important to indicate whether you are being hit or you hit the zombie. if you take more time to polish the zombie dimension, it will be a different game :D, it will be far more enjoyable I think. nice job for completing the game!