questions/answers about specific spells

[Jondifool]

Curse off stones questions
I will start with this one.

Curse off stones: battelfield (alteration 4 earth lvl 3, earth gems 3, fattique 300.

I finally got my mage to cast it,(how I miss a force the casting of spell X option, to override the AI.)

It does gives the targets i could observe more fatique , but how much?

And anyone have experience with when its really good to cast? maybe combined with some reinvigoriation on own troops or with other enemy burdening spells.