The Giant Red Slime monster is immune to magic, but Natalie's poison spell (which clearly states that it's magical in the tooltip) does direct damage to it!
I disagree that the hard badge should be an impossible badge. First time i tried it i got 130k and that was with 4 upgrade missing. second try i got to 366k and i killed myself because i got bored ^^
After almost 45 minutes of testing i have discovered that Ancient Monoliths have NON-ELEMENTAL ATTACKS. So there is no gear that resists their spells at all. Kind of overpowered if you ask me.
10% More energy vs 10% cheaper to build: For example, if you get 1 energy every second and something costs 100 energy. With +10% energy it will take 100 / 1,1 = 90,9 seconds to get enough energy. With -10% build costs it will take 90/1 = 90 seconds to get enough energy.
tl;dr : -10% build costs is better than +10% energy production
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