DDPlanner seems not to calculate the DU used in Pure Strategy correctly. This build takes 129/130 DU.
Build:
The stats listed are not the required, but the ones I had when testing build.
Build the buff beam on top of the "bridge" on the west side of it, at the edge, and the reflect on the east side, at the edge.
Ensnare Aura should reach the Buff Beam with Nature's Pylon.
I am not sure if it will reach it by building it where it's listed. I placed it closer and later moved it with Jester's Move Tower ability to where displayed when I figured it was a better idea.
All three damaging tower stacks go on top of the buff beam.
Depending on your Warden stats, you may not need to TB, but it is faster if you do.
Slight alternative build change: Instead of 4 Lightning Towers: 3 Lightning Towers + 1 Wisp Den + 1 Shroom Pit (130/130 DU used).
Waves:
First wave: Upgrader + TB. Max towers during this wave
Remaining waves: TB + Summoner with 2 Huntress Guardians
Last wave: TB + Summoner with 2 Huntress Guardians + Summoner with Huntress and Monk Guardians + Warden Builder
Notes:
Like mentioned before, the stats listed are not the required, but the ones I had when testing build.
With high enough status, you don't need TB but it certainly makes it faster. With my stats:
Starting at first wave (22) with the heroes listed below was smooth.
Upgrader
Summoner with 2 Huntress Guardians (Probably was not needed)
Last wave (35) with the heroes listed below was successful. However, it seemed at times quite overwhelming - but it was mostly just djinns. The cores were never in danger. It would have gone faster with TB and I do recommend TB. Lower damage output or bad luck with djinns despawning an aura and taking the Buff Beam with it is all it's needed for game over.
Summoner with 2 Huntress Guardians
Summoner with Huntress and Monk Guardians
Warden Builder
TB (Tower Boost was not activated, I kept one hero as TB just in case)