like, everyone say, red fly, if you not have a throw baby, only shoot it, one or two wave will be fine, but when you need face more enemies, it up→flyyyyyyyyyyyyyyyyyyyyyyyy→down, and you will lost, so you must have a throw baby
for PVZ2, the fly zombies, they up→fly→down, one by one, whether it face a whole line plants or interval plants, so even if you only have shoot plant, you still can defeat fly zombie