[sm0ke]

That would really mess around with PvP. Also are you still immune when the weapon is unequipped? What about if you equip after the spell is on? Or de-equip before the spell duration would have expired? It's just a bit of a headache, both in terms of deciding how it would work and also in terms of preventing it from breaking the balance of PvP, particularly 1 vs 1.

It wouldn't work if the weapon wasn't equipped only when you have the weapon on, I don't think it would mess with it too much if its balanced and made properly

@Habibi yeah those could work as well