Personal idea of mine: when the heroes go through Salem's lair, they have to fight grimmified versions of every dead lackey of Salem, and everyone killed by a lackey or grimm. IE, they would have to fight grimm versions of Pyrrha, Leo, Brawnz, Roy, Zedong, Fria, Sienna, Amber, Vernal, Tock, Adam, Tukson, Gretchen, Summer, Roman, and Ozpin (the host, not Ozma)