Aegis Protection and Banshee's Veil Interaction
Pantheon's passive blocks turret or basic attacks, and Banshee's blocks spells. Normally attacks would break one of them, but things like Ezreal Q (and probably Yas' as well, didn't test) would break both of them. They should really break one.
Not gamebreaking, but could use a change. Not sure if this was intentional or not.