Very nice tower defense game. It's fun to play at first, but it becomes boring at some point because you just randomly place attack towers (I didn't need the others) and wait. I think the game must become harder as you play, but it becomes easier, since all the zombies you kill give you more money so you can just sacrifice as many animals as you want and place as many towers as you want. (I know that this is very unintuitive but this is how it felt)
Overall it's a very well-made game and I like the artstyle, but it needs balancing and maybe additional game mechanics to force the player to use other towers and to make the game become harder as you go. And it could benefit from some sound effects and music.

I really liked the effect of the essence flying around

Thank you very much for those kind words.
Kuchenkruste and I feel the same way: The game needs more balancing, as well as some visual and acoustic feedback for the player. We surely had a lot of plans, but time ran out. Since it was a playable game (although a litte too simple) we decided to submit it nevertheless.