Instead of introducing Protobelt that has to be undertuned to not be gamebreaking...
... how about an active item effect that is purely for self-peel, just as the item was intended to function for mages? Mobility is too much of an universal tool, the only ones really building this item are AP assassins and not mages as they utilize mobility way more by default. Right now the item is so undertuned, not even Annie players really get it, even tho she would be probably THE mage to build it due to her very oldschool AoE-Mage-kit.
The thing is: do we even want protobelt to be strong? Because I got the feeling that this is exactly the kind of thing that is either "meh" or "HOLY SHIT THAT'S BROKEN", with little to no space in between.
The idea of giving mages some active item option was not a bad idea, but it could have been achieved without mobility:
Potential Item Active: Shoves all enemies a small distance away from you (in a circle with you in the center). Also possible: Gives a high, but rapidly decaying speedboost. (Cooldown Shared with other Hextech items).
This way immobile mages would have an item that would be truly tailored to them and not be as easily abusable by assassins who don't really need such an active as compared to the mobility.
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