Initial thoughts are that it's extremely laggy in game making just moving the mouse kind of frustrating, and at first glance I'm not really sure what I'm looking at.
The fact that the mouse didn't align properly with the pixel grid really bugged me.

Also mission 2 was unplayable and would just give an instant defeat as soon as I hit play.

I played for a while I really like it! selecting units is a bit fiddly and they get stuck on each other sometimes but if your careful its fine ^^ I get instant game over on level 2 is that normal? like I never see the map. Also I can't seem to win at level 1, I get game over when any soldier dies I think? I really enjoyed playing! :)

This is a very cool entry.

It took me a while to figure out what was going on because of the low res but once I did I had fun with this game. However, I did find it very difficult, specifically because of limitations in placing my soldiers, I felt like there wasn't a ton I could do to bolster the defense of one of my mines and I didn't quite understand if I was supposed to be able to move my soldiers or buggys/bikes. I did get a cannon down in a great position on level 1 that went to town on the aliens though, and that felt great haha. 

Visually I think it looks fantastic, especially with the lighting effects and all the different colours of soldiers and aliens and projectiles around the screen, and the music is atmospheric and engaging. 

I think there is a cool game here, it just needs a bit more polish to make it clearer how to play, but the core concept is really fun. 

Great job!

Great game!