@Sean_CGOL for the last level, i prefer alot of blues, being first to fire, so they can kill the ninjas before they go invisible. At wave 40 there's the invis ninja which can be killed with 5 meteors ( you need to max the skills for meteor ) and in order to have 500 mana, you need to have that skill which gives you 20 mana after creating a temple. You will save up gold and before level 40 you will summon many temples in order to refill 500 mana. The rest is easy.
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