Game Mechanics: Magician pets should not dual wield, or equip weapons before January 2000 patch era

[Khorza]

We discovered a bug whereby all NPCs will not utilize their "Dual Wield" skill unless they have a weapon equipped in their off-hand. Correcting this bug would cause all NPCs above the mid-20s to suddenly begin using their "dual wield" skill to attack players with their off-hand. This would cause a drastic shift to game balance, as most non-pet NPCs are generally considered balanced.

Wait so mobs aren't supposed to be able to dual wield unless they have a weapon in their offhand?

And why the mid-20s? Most NPCs would be able to dual wield from level 13 since most NPCs are considered warriors. And that's exactly how it works on P99.