Kleptomancy: Honestly just nerf mana potions and remove mana regen from looted biscuits
They are what is truly breaking the rune. It allows
to have exponentially increased lane staying power. The health potions and elixirs are fine, but the original intention behind both these champions' laning phase designs was for them to have safe ranged poke gated by their early mana caps.
But with looted mana potions restoring a whopping 100 mana and biscuits restoring 15% of missing mana, they almost never have to worry about mana issues at all.
If mana potions either gave only 50 mana or just didn't exist at all and biscuits didn't give mana regen as well, they would be alot more manageable to lane against and not just completely dominate the early game with infinite Q's.
The addition of
was already pushing the limits of previously mana gated top laners. At least
can still run OOM while spear-chucking even with Corrupting potion. But Gangplank was given a free pass with Kleptomancy.