my recent B-Serena Stuff (the 214A only connects if the 5C is a counter/fatal hit, which drains 1 bar)
5A > 5B > 5C > 214A - 1303 dmg, 4 hits, aerial rave starter
5A > 5B > 5C > 214A > jA > jB > jC > jD - 1663 dmg, 7 hits
5A > 5B > 5C > 214A > jA > jB > jC > jD - 1815 dmg, 8 hits
5A > 5B > 5C > 214A > jA > jB > jD > j214C - 2037 dmg, 8 hits
5A > 5B > 5C > 214A > jA > jB > jC > jD > j214C - 2133 dmg, 9 hits
Characters that get knocked down with B-Serena's jC (meaning you cannot continue after the jC): Herself, Sisca, Cletia, Cielo