I think it's just very well thought through! I thought it was game over for me when i ran out of granades but I was happy to see random mines being present. I would add some music and maybe some variation to the sound effects, there was a lot of them and after a while I found them pretty annoying.
Also, maybe I'm misunderstanding but you said you made a game engine during the jam? If so, super impressive but I have some doubts on how possible it is.
Overall, nice project! I would also appreciate if you could rate mine!