Borderline(shortened BL) are those banned to OU and up and cannot be used in tiers lower than it, Borderline 2(BL2) are those banned to UU and up.  This list includes pokemon that may currently be in a tier by usage but were at some point not, and banned from the tiers lower than it.     Borderline   Darmanitan Dugtrio Haxorus Lucario Kingdra Porygon2 Shaymin