Maybe if you try to cast some 'Lower Resistance' against Golems and then move on to damage spells...
Against dragons, cast the priest/cleric spell 'Magic Resistance', the spell will actually lower the dragons magic resistance, though the description says that it will increase... or maybe try to use the Mage's 'Lower Resistance' spell. Then cast 'Greater Malison' a couple of times, and last 'Finger of Death'...
I'm not really sure if this will work on your problem... it's just a suggestion.
