You'll need relatively high stats to be able to do this.
You'll need aleast 5k range on your monk to cover your defenses with a strength drain.
My apprentice has 5k Rate and 5k Damage.
Build everything wave 22 during the build phase and up the buff beam to 3 stars
You only need to upgrade the Lightning Towers
1) Put your auras over here, you don't need to resize them, just shove em in the corner
2) The second the other two crystals die, move the auras over as fast as possible. Move the strength drain first.