I hate to say it but...I really don't know what to do? There are upgrades, but I don't have enough whatever to upgrade them; these guys come out, but I don't know how to attack them or...Is it tower defense? Should I buy a tower, or try to kill them myself? And anyway what are the controls? I used the arrow keys but I have no idea what else does stuff...
Use Spacebar to shoot a fireball. All enemies have 1 hp so it should be a 1 hit death. If you kill them outside the rune circle they'll drop a soul, which you can use to purchase upgrades...I didn't have enough time to add a tutorial level sorry about that. I've updated the game description with the controls.