Nice game. I liked the music and character models. As others said I feel like this game could be fun its just needs couple of fixes. Even after reading the tutorial on the page I was still a little bit confused about the controls. I think there is a mistake in the game tutorial where the mouse buttons are swapped. The controls are also sometimes unresponsive. In the first level the enemy at one point just got probably stuck next to the wall and couldn't move at all. In the second level sometimes I didn't know if I clicked on the triggered a crystal breaking or not. Also I thought for a while that I am loosing units, until I realized that the units were just stacked on top of each other. At the end I managed to kill all the enemies, but didn't recieve any option to move to the next level so I had to go through the first level again.
I really like the idea here, but it would need a slightly better tutorial, more precise controls as well as more sfx. I would also suggest maybe showing how many units are selected.