The build is designed for AFK in mind for the last 3 waves. It's not the fastest possible run, but it's still a decent run time. For the waves, I do 2 guardian summoners (spped + range), one for each tower stacks, 1 tower boost monk, and builder apprentice. For the first wave I only do 1 guardian summoner buffing the LT stack, and I use upgrader to max towers.
The monk tower boost should last until the last 5-10 ogres usually, but even if it goes down and you're afk it will still be fine, will just make the run a bit slower if you dont tab back in to start tb again.
There are more DSTs pointing toward the north because of the stuck ogres at the end of the wave.
The thunder spike trap is mostly for spiders. I did get my towers webbed a few times (still rare), so I place that there to fix the problem 100% of the time.
Same with the double reflects, sometimes Cyclope spit ball just goes through reflects for a weird reason, so I decided to do 2 layers of reflects, and that fixed the problem 100% of the time for me.
For the south aura stack, downsize the ensnare. For me it's 3 sticks down.
The walls are slightly angled to make it so ogres can't cleave the core.