Nice, thanks for playing!
These are skill buttons, try using them in a pinch. Some activate on press, others you need to press the button then aim with mouse.
Ah, cool. Just FYI. Those enemy troops are stuck between those two peaks. One at a time would come out of that cluster and that's how I stayed alive for a lot longer. So the enemy is getting stuck in the landscape when bunched together like that. I don't think I made that super clear in my last comment. Cheers and happy coding!