Modding

You might be right. I noticed an interesting nuance regarding absolute magic: it removes magic resistance and magic protection from all creatures that are damaged by the spell cast by the hero. For example, Marbas, with almost 100% magic resistance, always dealt damage with his spells to all his troops with increased damage. As soon as I removed the perk for absolute magic, in all other cases, magic resistance took effect when the meteor shower hit his own units.