[1.2f] Autoresolve uses magic with no regard for mana
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Elemental Forums
See following picture.
http://dl.dropbox.com/u/32649007/Elemental_1310314332.jpg
I had 16mana when fight began, then autoresolve used mana like 5-6 times for an 8mana spell. After the fight, I still had 16 mana.