(Magic: The Gathering) Being a card which is black and no other colors.
(Magic: The Gathering) Being a deck composed of only black or colorless cards.
1996 April 16, Daniel Gray, “Re: Some Type II strategy”, in rec.games.trading-cards.magic.strategy[1] (Usenet):
"The Black Problem" has two good, easy solutions-- the obvious one is Whirling Dervish, which no monoblack player can block, and can only be gotten rid of with Disks or Icys.
1997 February 10, Jesse Chounard, “Report: Pro Tour Paris PTQ”, in rec.games.trading-cards.magic.strategy[2] (Usenet):
He was playing a monoblack weenie deck with 30+ creatures in it.
1999 May 3, Eric Taylor, “Re: To all the Jamie W. lovers”, in rec.games.trading-cards.magic.strategy[3] (Usenet):
You can talk to him all day about how good high tide is in extended, or how good necropotence is in a monoblack deck, but he will still never play it.