These cards are kind of weird. They are clearly meant to work together, but obviously, you can’t have each side available to you at the same time, so you need figure out how use both sides. I’m not going to do that. Basically, I’m making a horde deck, which tries to grow the creatures though black’s ability to gain life consistently. It is also possible that Valentin is itself a nice plan in certain contexts, where graveyards are well used.