change attribute

is there a card that can change all of the monsters attributes in the graveyard to dark? If yes can you tell me the name if not can you tell me good dark attribute monster and hove i can get about 7 or more in to my graveyard

no, for now no card for that purpose.
Dark Attribute monster is usually good, DaD, Chaos Sorcerer, Junk Synchron, etc.
Try veil of Darkness maybe?but, this'll probably kill the purpose...who knows.

hmmm Veil Of Darkness is just the card i needed gives my draw power and help me get darkys in grave

there is dark grepher, armageddon knight,too.
also,i think card trooper is good .