#1 In my playthrough the Wyverns flew low enough that they got caught in the auras and in the Inferno trap, so nothing else was needed there.

#2 Important to slow down the Wyverns here, allowing the turrets enough time to target them and take them out.

#3 This was a popular spot for assassins so in the later rounds I had to beef up this area.

#4 A lot of the turrets here are positioned to cover both paths for wyverns, this made sure nothing made it to the core the entire run.