CotBG is excellent and probably the most essential addition to the V5 game line. It collects all of the clans of death, now condensed into bloodlines under a single 'family' clan, the Hecata. This book is big, it has the Harbringers, the Samedi, the Nagarajah and yes, my favorite clan of Revised edtion, the Giovanni. Included are rules for their unique discipline of Necromancy which now falls under the purview of Oblivion, tapping into the powers of the Underworld to fuel their necromancy; thematically one of the best representations of this power in any edition of VtM, (yes, it should taint your soul). Additionally you get Loresheets to represent all of the death clan bloodlines in the event you want to play a more unique vampire. You get a great story that focuses on these clans, though you dont have to be Hecata to play in it. Onyx Path delivers yet another steller book to expand the core rules of V5 and I hope to see more.