This build has been tested with 5k main stat heroes. It is made to be as safe as possible especially when your tower boost goes down.

Build Note 1: The two spider minions are there to deal with the occasional ogre. I found the runs to feel much safer when I had them in.
Build Note 2: The reflect beams are there to protect your towers and Tower Boost Monk from spiders. Getting webbed and not paying attention is the reason for most of my failed runs.

Waves 22-34 Note: I was able to maintain tower boost through the entire wave.
Waves 35 Note: I stop tower boost at mob count 1900 and then start the tower boost after cool down to handle the final Genie/Sharken rush.
Wave Note: I used a tower boost monk, two Summoners with Apprentice and Huntress Guardians, and the builder Warden.

Hint 1: I put my builder Warden on top of the Golem. I was able to make it through all waves without dying.
Hint 4: My Tower Boost Monk stood on the Warden towers and shot at hint 4.

Arrows
Blue = Cloud direction

Video
Maybe...