So when i first jumped in i struggled, especially not realising i had to buy the dash, but once i figured out the slide + jump combo i began to really enjoy myself.
this game really shines in the movement, once you've got some upgrade going it becomes really fun to slide, jump and grapple your way past the hordes and go for that sweet long range lob of a box into the chute.
For me, i feel like starting out with more movement would be a much nicer entry gameplay experience, perhaps not needing to unlock the dash or a small tutorial to show off the movement concepts, and maybe less zombies to begin with while the player learns the ropes.
The art is fantastic, the loading screens with concept art superb.
My only other feedback i could give is sometimes i wanted to go for a crazy lob of the box while travelling away from it at speed, and turning around for the fade away shot - but i felt like the box kept your momentum and would sometimes fizzle throws - makes sens physics wise but gameplay wise i really wanted to lob that box :P
Oh also would love to be able to buy more grapples - i think their current form it makes sense to be limited as they made it op to get to certain locations, but the combination of grapple + slide and jumps is a strong one and i really wanted to do it more, maybe even grapple to walls / etc
Realy cool premise also! Great job :D