Quick guide for the easiest walkthrough ever:
1) Grind 1st level until you buy all available archers (you buy additional archers by adding one point to their health)
2) Grind again until you buy all levels of Bash and Attack Speed on all archers.
3)Buy the other special arrows and archer damage. Then upgrade activated skills and rotate them when convenient.
2/5 This game has no tutorial, only one background song and a nice graphic. Plus, I've been playing over one hour and it's the same thing. I got 36 upgrade points w/o use. Does this game have an end?