[Folket]

For Niefelheim to cast anti magic you would need a rare S2 Gygja or a Gygja casting power of the spheres and then sleeping a turn before casting anti magic. Arco should be able to kill the Gygja with magic duel.

I would like to compare lightning spells to fire spells against Niefel giants.

Niefels with E9 blessing have 18 in protection. Could be more in cold provinces.

Fire darts, evocation lvl 1. 3 x 15 damage against niefel giants. That is 18 damage after armour.
20 fatigue. F1
range 25+
precision 4

lightning bolt, evocation lvl 2. 14 damage
10 fatigue, A2
range 35+
precision 4

Two out of three mystics will be able to cast fire darts. I do not see why I would like to recruit an oreiad for 400 gold to get some more range over a mystic for 150 gold.

Seems to me that most things will be cost effective against niefel giants this late into to the game. Earlier in the game it would have been hard to mass the mages needed.