>>96798217
I'll put it this way.
Color identity is this card saying he's white because he has white in his effect box. White cards might hang out in the same deck as him, but he doesn't fit in monoblack decks.
Color is what his manacost and typeline state. Unless he undergoes Micheal Jackson surgery from Eight-and-a-Half-Tails, he still dies to Mass Calcify.