I don't understand. BL Pokemon say they are in OU, the same for BL2 Pokemon but they are in UU. And what tier is Gothitelle actually playable in?
Borderline is a Semi-Tier for Pokemon that can fall by definition cleanly into both OU and UU, not just a UU Poke being used in a higher tier. they are anomalies that can't be classified as UU because they have all the criteria for being OU, but also are just as evenly qualified for placement in UU. however BL only really is looked at during major competitive events in an effort to help regulate tiers better. and Kingdra need to be BL. just sayin