Pain Td G3 update

I am working on a tower defence where I decided to combine td with a some elements from dungeon keeper. First few versions of game didn't do well because I couldn't find right balance. But after some trial and error I came much closer to solid foundation for my game. I made game play slower paced, enemies tougher but less in count, and all basic towers can be upgraded, nothing big but I like the way it goes.

I also update sprites for all enemies and some towers.