Great game ! High score : 75000 !
The game is really enjoyable and polish, it feels good, I encountered no bugs at all, and overall it just feels great to play !
I have some suggestions for you :
-Power-up would be useful, such as being able to collect everything in one click, but every 30 seconds or so, or a damage spell to clear. Some times the game becomes really hard to manage (but in a fun way :) ) and some power up would relieve some stress without removing to much difficulty, or at least I think so.
-A larger vertical map : I feel like sometimes it is really hard to place units due to the lack of space when you are surrounded by the survivors, and having more place in the upper or down part of the screen would be welcomed
And that is it for me, thanks for making such a great game, and I would love to see a game like this continued to be developed, because the game concept has a lot of potential