I ask this question because it seems at the moment to be the easiest way for me to win battles that seem otherwise balanced.

I have won battles against groups of things that have 10+ attack each by casting wither multiple times until they have 0 attack.  It would have been a close battle if I could only wither once.

Additionally I took down some epic dragon from an inn quest that had over 250HP.   I cast obscuring mist about 10 times with 4 different heroes, and by the time the dragon got around to my second group of units they were dodging almost every time.   I then cast berserk on one of my spear groups designed to avoid armor and do a ton of damage.  Half of the dodge going to each units attack made the group hit for over 120 a shot on the poor dragon.   I feel this was an unintended use of the spells??

Or is this a balanced because:

A)I had to have 3 or 4 heroes in one battle that could cast obscuring mist

B)I used about 120 mana

C)Got about 3 units of city militia killed

D)Had the dragon attack the city where I had better defense

Perhaps all of that is worth about one epic dragon??  But really I only lost 3 garbage units that replenish themselves if I'm not mistaken. I haven't really got a good enough grasp on the overall balance to decide either way.   I'm leaning toward overpowered because it seems like I progressed past some fights faster then they were intended.  Thoughts?