The idea of this game is very random and funny XD Going around with a digger to kill zombies. The execution is nice as well. The controls take a second to get used to because of the crane that rotates seperately (also in the tutorial it says to use ASDF to move, instead of WASD), but I think that is fine! The way the camera was a little bit nauseating to me. Nothing too bad, and I was able to play the game just fine, but I can imagine that some other people might find it more disturbing. (Unfortunately I also don't really know what is the problem :/)
The art was really cool! I have never made a 3D game myself, but when I do I will also start with the lowpoly style. In that case, this is a great example to take inspiration from! I agree with others that a bit of music would have been nice for the atmosphere. A few more soundeffects for feedback will also help I think.
I really enjoyed this! Great job :D