Wave 1: Build everything and as many owls as you can. Use TB on p2 to drop mana to finish building the rest of the owls. Try to max out Buff Beam.
After that, just do builder Guardian + TB, aiming TB at Hint 2. On last wave, pull out 2x Huntress and 2x Squire G.Summoners.
Obelisk only focusses on the left lane, you could move the stack more to the right so obelisk can hit both lanes. Not needed.