Thanks for checking out my game. The end condition is the left bar goes to 0% or the right bar goes to 100%.
Right bar is remaining HP essentially, left bar is how many people have died without being reaped.

Thanks! It seems you may be right about the difficulty, others had trouble as well. It's supposed to a high score game, but perhaps giving more time and slower despawn timers for the humans would make the game more fun. I decided to develop this game a bit more so I'll take that in to consideration.

Haha yeah we had quite similar games!