[Amergin]

i dont know about azred's golems, but ive taken out adamantite golems with sequenced lower resistances and magic missiles. there is no way to deny magic resistance lowering spells; they would be pointless if there were. the only thing that stops them is a spell shield, which golems, of course, do not have. i have no idea why your clay golems are resisting it.

however... if you are casting Pierce Magic from the Wand of Spell Striking i CAN tell you why it isn't working. an item has two ways of "casting" a spell depending on how the designers worked it: you can "cast spell as mage/cleric" such as how Daystar casts Sunfire or you can just duplicate the effects as is done with the Wand of Fire. the problem arises specifically with ranged magical attacks as there is a "damage type" parameter and for most things ranged, including weapons, this gets set as "piercing" so anything immune to piercing "damage" would also be immune to a magical effect using this parameter.