I mean look at the team comp, only reason you would build BC here is to counter Alistar, hence cleaver being an item for shredding tanks. And yes, ussaully you build collector when fed, that way you can snowball incredibly fast and then end the game. Ghostblade is also a good item on graves, but you also gotta look at the team comp. You ussaully build it when your against bruisers and CRIt champs.
