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When I play all armored endurance, I get 3 areas set up: I did this for the first time on H11, and ended up with a total multiplier of 7583. For example, it takes about 4-6 grade 19s in a shrine to kill off a monster with 3 billion HP, so save yourself the trouble. Get your amulets done early on in the battle.Remember: Don't summon after round 160 or so.Put a blue/purple trap before your YOL trap until you're comfortable that your YOL can kill anything (grade 20-21 or so).The nice thing about this is that the max natural creep HP stays at 3.33 billion for the rest of the game. Do not summon after 160 or so, since the natural HP of the creeps quickly starts to climb to 3.33 billion. You make a huge profit by doing this, since the giants are worth so much per kill. For me, it was 1 gem grade per 10 waves, so 1-10 is a grade 1 gem, 11-20 is grade 2, etc. The second key is to use Giants Only and summon as many as you can handle each wave while you're still setting up. You'll have to 8x-Amp a single tower for a while before you have a high enough gem, but once your YOL gem is about grade 12 or 13 you can put it in front of the entrance and instantly fill your mana bar with dead monsters.
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The first key is to get a gem that is Yellow-Orange-Lime. I'll re-paste the mini-guide I posted on JIG here:
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It's not that hard once you have it set up right. I was one of the first people to beat endurance mode (level 1337) on Armor Games' leaderboards.
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