Dark Ritual effects one-shot bursts like Dark Ritual, Cabal Ritual, and Songs of the Damned for explosive early plays Swamp-scaling engines Cabal Coffers, Crypt Ghast, and Nirkana Revenant multiply mana based on your Swamp count Life-to-mana conversion K'rrik, Son of Yawgmoth and Bolas's Citadel let you spend life instead of mana Sacrifice-based mana Phyrexian Altar and Ashnod's Altar convert creatures into mana for combo turns Treasure generation Revel in Riches, Black Market Connections, and Pitiless Plunderer produce Treasures tied to death triggers Building a Black Ramp Package Mono-black ramp packages should be built around the Coffers engine: Cabal Coffers, Urborg, and 2-3 Swamp-scaling payoffs like Crypt Ghast and Magus of the Coffers

(There is psychological value to countering an opposing spell with a Force Spike since they are so easy to play around, yet it's not worth playing around them in Commander because they aren't heavily played, which makes getting your powerful spell hit by Jwari Disruption especially devastating.) As for the rest of the bunch, Silundi Vision is listed as an often play just because you need to be a reasonably spell-heavy deck for it to work
The ability to sac sub-optimal hatebears that we draw by chance into relevant threats and pieces of disruption is great
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It has enhanced value in self-mil and recursion brews, but any deck with dorks that runs this color should run it, and I love it in midrange getting back a Ravenous Chupacabra or Flametongue Kavu or even a Karmic Guide to get another dork like your Grave Titan or what about that Sun Titan to get back your Reclamation Sage