Is located on the edge of the roof above the crystal (Use Genie Lamp to teleport on top). Green Arrows are directions for the cloud towers, the minions are placed on the stairs on the east side of the crystal and on the entrance ramp to the southwest side of the crystal.
Hint 2:
The auras are placed on top of the cart just south of the crystal to get some more height. Blue Arrows are directions for the cloud towers, the minions are placed in a wall just south east of the crystal with the first minion touching the cart the auras are placed on.
Hint 3:
Yellow Arrow is the direction for the cloud tower, the minions are placed in a wall to the east of the crystal.
Monk Tower Boost (TB) on the roof located at Hint 1 every round.
I used Apprentice Upgrader starting at Hint 2, then Hint 3, then Hint 1.
After everything is upgraded I brought 3 additonal Apprentices in with a Huntress Guardian and placed them at each crystal since I was farming Emerald staffs. (Resistance will be needed if they are at Hint 2 & 3)