Because purple is now allies with blue and black, those two colors are no-longer allies with eachother
But even if you dont control a Demon, you can still draw a card once per turn (losing two life points in the process)
A very easy condition to meet, but you can't twinkle toe around it, you have to put in the work
8 Shichifukujin Dragon One of the oldest cards on this list, Shichifukujin Dragon was printed in 1996 as part of the celebratory opening of the now Japan DCI Tournament Center in Tokyo
Skeletal Scrying The downside of eating your graveyard to draw cards is maybe worse in black than any other color
Arcane Denial, Brainstorm, Inscription of Insight, and a personal pet card of mine, Minds Aglow all help shore up your draw engines