Thanks for the feedback!
And yes there is, just as that video points out, I did a poor job showing things. While the "hero" keeps leveling up, I put a cap on their stats. Their damage will keep going up, but their attack rate and "bounces" are capped. Attack rate is capped to 5 shots per second and bounces to 2. And their damage only goes up 1 per level, which you can outpace pretty easy with upgrades. And once the hero levels up, it takes twice as long for them to level up again, so they really slow down in power as the game goes. Even with multiple "heroes", you can eventually overwhelm them no matter what. I really only tested up to 3 "heros", but I imagine you could keep going and keep wining. You know, until you break the game by the amount of stuff that spawns haha.
I plan to put out just a small update by the end of tomorrow to just show things better. And if I have the time maybe add in some features ;) This game wasn't meant to scale and be expanded on much, so adding things is a bit hectic to say the least. But hey, if the engagement keeps coming, I will happily start from scratch and make something much cooler!