Build instructions:

• Wave 1: Take your time so the crystal can move past the south spawn.  Collect all chests, build traps, wall, buffs, and minions.  Add AFK ranger with monkey on crystal.  Switch to adept+genie and 'g', spam LTs on beam.  (If you can't stack, make a longer beam and make more room for LTs.)  Upgrade both buff beams.
• Wave 2+: Switch to upgrader; switch to DPS huntress once LTs are fully upped.  Place more darkness traps at Hint 1 after the north buff goes down.
• Final wave: Remember to switch to huntress if you want a BF Drill.

You will likely need a DPS char on the first wave to protect the crystal, so bring a friend.  This build is very fast.  If you have 6P every wave, the crystal will end up almost reaching the LTs when the final wave ends.

This build uses ideas stolen from multiple players including Pjtor.