Make Ohmwrecker an AP item.

It’s useless on tanks anyway since they would rather buy items that give them more health, armor, or magic resist but I think the active would be great for mages. Sometimes when I tower dive as a mage I get frustrated when I die because I was so close to having an ability available again. “But mages would rather buy items that give them more damage to kill them in tower quicker or buy zhyonas to survive a turret shot”. Ok fair enough so to help the item be more valuable and unique, maybe you can also use the active on ally turrets to give you a shield to help survive tower dives against you instead. Plus this would be a great item to compete against ad assassin items since all the fun assassin items go to ad champions instead of ap.