Nice tower defence, it feels satisfying to improve the defences and see the zombies get impaled on them!
The tutorial is a great touch, it helped me a lot :D
In term of juiciness, I think a lot could have been added, the VFX are cool, but I would have lot to see the enemies become ragdoll when they die, screenshake when big towers shoot, more particle effects everywhere, enemies losing blood or flashing red when they get hit...
I wasn't sure what the most expensive turret does.
The packs that where used are very cool and the game looks really great!
It's a very cool game and I had a lot of fun playing. Great job!