There's a way to solve the synergy between physical damage and magical armor without adding RNG back to the game:
Add both armor values to the health pool. Make the attacks deal damage to both health and the proper armor.
Eg.: Current target has 200 HP, 100 Physical Amor, and 150 Magical Armor.
After the change, same target will have 450 HP, 100 Physical Armor, and 150 Magical Armor.
If someone attacks with a fireball that deals 50 damage, the target will be left with 400 HP, 100 Physical Armor, and 100 Magical Armor, thus, not getting burned because it has Magical Armor left.
This change might increase overall effective health to enemies, since a party composed solely of physical damage or magical damage would be able to ignore the other armor, dealing less damage overall to kill a target. However, I believe this is a good change, since it would make hybrid characters or diversed parties more optimal, while also allowing necro to be more usefull overall. Not only that, heals would also be more valuable, since hardly someone would be full health. Maybe some talents would need some rework (like Hot Head).
Another solution for those who actually like RNG is to make the same modifications, but adding the % chance-based on armor left CC's, like many proposed already.
