Units consist of several sprites and sometimes they fall into each other.
"What if I kill said "unkillable enemies" with meteor bonus(es)?"
I think about this. There is two variant:
1. Make endless unkillable enemies in the end of wave, that guaranteed destroy player base.
2. Give possibility to kill this unkillable portion of enemies with bonuses as now. Because if player use bonuses in the beginning of wave most likely he will win. So what's the difference when he use this bonuses)
It will be great if you have any idea how to improve this mode.