It's bad enough I have to watch ads at the start
Fun, innovative gameplay. Thumping beat. Good upgrade system. All this ruined by the game suddenly pausing and playing an ad. If you had an ad pop up, say, every time you leveled that would be acceptable. Maybe in between every 10 waves. But in the middle of a wave? No. I can forgive a lot of things but an interruption like that is intolerable.