1st Strategy :
Before Elements , build 2 cannon towers first at the entrance or near the middle (not in the middle) .
1. Get Light Element
2. Get Earth then upgrade to quark tower.
3. Get Dark . Upgrade to laser get it alternately with the obliteration (you can choose if you want to build laser or obliteration first but i recommend obliteration)
Note : Never get Fire in early game .
4. Build Trickery as you build laser . Get Nature . Build Obliteration 1 time only for splash .
5. Build Enchantment tower for bonus damage . Get Water for attack speed .
6. Obliteration is just for early to mid game like round 30 you dont need to upgrade it to max .
7. Get Light element again then dark element so you can upgrade it to the max level . Now you can build eidolon early . Build atleast 4 .
8. Get Earth lvl 2 then upgrade the laser to phasor . As you complete every round upgrade the laser to phasor and enchantment to incantation ALTERNATELY . (phasor first)
9. You need 8 Phasors with Eidolons so you can have 16 Phasors (the half is illusions : lasts 60 seconds)
10. Now get Fire so you can buy the Periodic . Otherwise you cant beat the boss round 3-5 . Build 2 Periodic Towers . Last support tower is the Blacksmith Tower .
Note : Boss Round doesn't give any bounty/gold as you kill them .
I tried it many times , I always survive . The problem is the early game , some of them can go to the exit if you dont get obliteration early . Phasors deals 30k damage so if you have 8 of them + the illusions then you can deal very massive damage also 2 Periodic Towers got Illusions . You better put them mostly in the middle part and between entrance and exit so their range will be useful everywhere . Do not build at the bottom part .
2nd Strategy :
1. Get Nature . Build Nature and 2 cannon towers.
2. Get Light . Upgrade to Life tower . Build 2 of it .
3. Get Dark . Build Light then upgrade to Trickery . Upgrade a Life tower to Obliteration Tower . Better if you put it Between the Entrance and Exit .
4. Get Earth . Build 2 Light towers then upgrade to 2 Laser towers .
Continue reading above starting on Number 5.
It can reach until Round 56.
Add me in game . ID : 163303222 . Thanks for reading !