Help. . . .

So I didn't play the game for a lot and bruh everything is way harder, I am struggling to beat the fallen mode when back in the day it was a casual thing. So I wanted anyone to tell me the new choke points in the fallen mode so I can finally beat it.

I am 162 level and I have every tower except necromancer, engineer, and gatling gun(I don't remember it's name) Idc if this helps