Thank you for your feedback, by hitting space you can be necromancy yourself (not spawn enemies) they will fight the enemies for you. I was going to add a cut scene / tutorial and add juice (which I have done in other games of mine) but I didn't find time for it trying to polish the core gameplay.
The lag is just me reducing the Time.timeScale to 0.1f with screen shake. I though it looked cool, but it might look a but jarring (also when ever you hit enemies there is a little screen shake).
Thank you :D