For anyone trying to go far on endurance mode, the easiest way to go far is to do it on armored only and however many other multipliers you think you can handle. Then, start with a tower or two to destroy the beginning monsters and to get your mana up (anger if need be). Then, create a Lime/Yellow/Orange trap and surround it with six amplifiers (look for corners or straightaways). Then, start mana farming. Make sure to shift click your mana spell so it automatically is cast when your mana is full and then just upgrade your trap, keep either the same or 1-2 grades lower in the amplifiers, and then just sit back and watch.
@Rannen It's for endurance mode. After about 120+ waves, red starts to lose the edge that it has with lower levels when it comes to attack power. The reason why people say that Lime/Yellow/Orange is the best is when it is put in a trap and it is surrounded by six amplifiers, the specials are boosted extremely. By grade 9 or 10, I (I'm a premium 30 something) have a gem with 100% 5x damage (Yellow), 100% chance to hit 5 targets (Lime), and ~4x whatever my mana multiplier is. The Y/L/O Combo is better than using red with anything because the multiplier isn't dependent on the kills, plus you start getting flooded with mana at "high" levels (100+)
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