I can confirm what Zhuangzi said.
At 39 int, my rain of fire was hitting for like ~4k. My armaggedon was just above the 6k barrior. And don't forget lightning bolt. Very nasty for opening a battle.
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I took out the last boss, the dragon circle, using demonesses with agna's (Which allowed me to act first), and insta-gib the entire army using 2x armaggedon for 6k each. This was as a mage.
Now tell me mage spells aren't powerful 
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