Don't make the music loud af in the menu with no way to turn it down
That alone is worthy of a thumbs down

Wolfenstein with better (just barely) graphics and worse controls. If you get a kick out of insanely difficult and repetitive gameplay then by all means jump on in.
Allow my to qualify by saying the levels you walk around shooting or slashing zombies aren't hard at all, just be prepared to do the same thing for an extended period, which I can do, so that's not really a drama.
It seems like you can't short-cut the levels (not that it worked for me, anyway) At the end of the first stage you need to collect batteries to recharge the system, BUT, after all the zombies were returned to the land of should-be-dead I collected the battery and strolled back to the start position where upon I was told that I needed a battery. What was wrong with the one already tucked under wing I'm not sure but I couldn't insert that battery in anything. I tried lube. butter and brute force, all to no effect. It seemed my only option was to restart the game and go through the process in a linear fashion (ie. wipe out zombies, return to the battery receptacle, be told that i need a battery, fetch said battery, return with aforementioned source of portable power) and ,Ta-daa it accepted the very same battery I had offered earlier. Repeat 3 x to finish first level.
2nd stage was different so I thought to myself "Self, this could have some hidden value, let's press on."
3rd stage was the same-ish as the first.
4th stage however, 35 minutes of trying to beat the Goliath was enough for me, and thus endeth my interest and time investment in this little frolic.
I appreciate what the creators are trying to do, and for the most-part it seems to work, so congratulations are due for the effort but I can't really suggest you give it much more than an hour or so of your life.
I'm glad it was free.