BWx Clerics has potential to become the go-to Aristocrats/sacrifice archetype upon rotation, especially since Rakdos is losing Mayhem Devil and Zendikar Rising brings a few neat card choices to the table. With that said, I'm unsure if Clerics as an archetype can reach top-tier status. At present, it seems as though there are a lot of building blocks for a synergistic, value-oriented deck, but no fast aggro potential or big combo-kill finisher (a la Mayhem Devil/Bolas's Citadel) that could catapult it into the S-tier. So the question is: will BWx Clerics be the new Rakdos Sacrifice, or will it be confined to B-tier status amongst a meta full of Dimir Rogues and Temur Clover? Let's discuss!

Colors:

Black and white are the key cleric colors and get a lot from Zendikar. There's not much in blue to tempt us. Red has no clerics but does give access to [[Claim the Firstborn]], which has been a staple in these decks. Green adds [[Conclave Mentor]] and some fun support cards -- most notably, [[Nissa of Shadowed Boughs]]. Overall I think straight Orzhov is the most viable archetype now that shocklands are rotating, but Mardu and Abzan are worth exploration.

Sample decklists: (manabases and sideboards probably need work)

Orzhov Clerics

Abzan Aristocrats

EDIT: Orzhov Vito might be viable too. Goldfishing with this thing, a T4 kill (Speaker>Nullpriest>Vito>Elspeth) or T3 Angel token (Speaker>Aspirant>Demonic Embrace) is pretty viable.

Card choices:

Clerics:

Pre-Zendikar, there are only a few clerics we really want to play (shed a tear for Priest of Forgotten Gods...):

[[Archfiend's Vessel]]: Looks like an auto-include in any Aristocrats-type deck. Blocks/beats early and reanimates for value later on.

[[Speaker of the Heavens]]: Potential value generator, but I'm not convinced it's consistent enough to run. The token generation seems like it'd only happen when we're significantly ahead anyway. That said, a vigilance lifelink creature is still a decent 1-drop in some builds and there's a lot of lifegain in this archetype.

[[Vito, Thorn of the Dusk Rose]]: I'm on the fence. There's enough lifegain floating around to be tempting, but he's very, VERY underwhelming without support. Unless there's a lifegain combo-kill out there that I'm not seeing, I don't think he makes the cut. (EDIT: There may be a viable lifegain combo-kill deck. See the Vito Aggro decklist above)

[[Mangara, the Diplomat]]: Meta-dependent, but I can see this being in the board if go-wide aggro is a thing. It costs 4 though, which isn't ideal for stalling aggro.

[[Conclave Mentor]]: Might have legs in an Abzan counters-oriented variant.

[[Acolyte of Affliction]]: Fits the general "graveyard matters" theme, but it might be a little costly for what it does.

Most of the best clerics come from Zendikar rising. In no particular order:

[[Nullpriest of Oblivion]]: Solid beater and a VERY relevant kicker.

[[Luminarch Aspirant]]: Lots of hype, but I'm actually on the fence on this one. [[Ajani's Pridemate]] never really took off, and this doesn't look substantially better. That said, in more aggro-oriented builds or Abzan builds with Conclave Mentor, it could find a niche.

[[Cleric of Life's Bond]]: Also sort of reads as a worse Pridemate, and I'm skeptical of it for that reason. That said, it does generate more value off of reanimation shenanigans and repeatable lifegain is synergistic with Speaker.

[[Taborax, Hope's Demise]]: This, along with Orah, seems like a prime reason to play this archetype. It's an evasive Midnight Reaper that gets bigger, what's not to love? Lifelink is probably its least relevant ability; by the time it turns on, you probably don't need it anymore.

[[Marauding Blight-Priest]]: Maybe, but unlikely. There are probably better 3-drops around and this one doesn't generate all that much value.

[[Orah, Skyclave Hierophant]]: Another value engine, and central to the Aristocrats plan. Any cleric that dies activates Archfiend's Vessel. Also offers some wrath protection.

[[Tajuru Paragon]]: Possible in an aggro-oriented Abzan variant. He triggers Taborax and Orah, and he digs for more dudes.

[[Drana, the Last Bloodchief]]: Repeatable value engine, but it's also a 5-cost creature with no ETB or immediate value. My gut is to pass on this one.

[[Scion of the Swarm]]: Another 5-cost, no-ETB creature. Pretty unlikely, but worth a mention.

Creatures that I considered but didn't seem worthwhile to discuss include [[Niambi, Esteemed Speaker]], [[Venomous Hierophant]], [[Victory's Envoy]], [[Anointed Chorister]], [[Attended Healer]], and [[Demon's Disciple]].

Non-clerics:

[[Woe Strider]] and [[Lurrus of the Dream-Den]] (maindecked, not as a companion) are pretty likely candidates in a deck like this.

Abzan variants will likely use [[Grakmaw, Skyclave Ravager]] to great effect as well.

[[Nightmare Shepherd]] and [[Luminous Broodmoth]] are worthwhile mentions as well, to get more value out of the sacrifice theme of the deck.

[[Serrated Scorpion]] has been a mainstay in these decks, but I'm not sure it's a good fit here. Still, it blocks early and it might be the best early-game enabler for Speaker of the Heavens that we have.

[[Pharika's Spawn]] plays nicely with both the graveyard-matters theme and the 1/ 1 counters theme. At the same time, it's a little slow. It might be hot SB tech against Rogue mill, though.

[[Swarm Shambler]] in the Abzan counters variant.

[[Nethroi, Apex of Death]] is a possible top-end beater, and gets sort of dumb if you have a [[Polukranos, Unchained]] in your yard.

Non-creature spells:

[[Village Rites]]: Auto-include. This and Woe Strider are probably our two best sacrifice enablers.

[[Call of the Death-dweller]], [[Thwart the Grave]], [[Malakir Rebirth]], and/or [[Agadeem's Awakening]]: These fill a similar niche -- recurring value creatures, and especially Archfiend's Vessel. At present, I'm unsure which is best, though I'm leaning towards CotDD for initial decklists with some Rebirth sprinkled in.

[[Bastion of Remembrance]]: Another one I'm unsure one. Fun with sacrifice shenanigans, but little immediate value. The fact that the token isn't a cleric might disqualify this one.

[[Relic Vial]]: Possibly better than Bastion, not convinced it's a better sac outlet than Rites or Strider. Maybe worth testing, but I'm skeptical.

[[Nissa of Shadowed Boughs]]: Counters, reanimation, and extra attackers. The Abzan version should run at least 3 of her.

[[Elspeth, Sun's Nemesis]]: Initially I didn't include her, but in a Vito build she can get scary quick and all her abilities are relevant.

[[Demonic Embrace]]: Good utility, and can be cast from the yard. Bit of a nonbo with Broodmoth, though.

[[Claim the Firstborn]]: The only real reason (besides [[Cinderclasm]]) that I can come up with for a Mardu build. Still phenomenal value when paired with a Woe Strider or Village Rites. Though, Claim and Broodmoth are a nonbo and a pretty egregious one at that, so brew accordingly.

[[Eliminate]], [[Heartless Act]], [[Hagra Mauling]], spot removal generally: The immediate post-rotation format is likely to be overrun with rogues and aggro and so I plan on packing at least 3x Eliminate somewhere in the 75. The correct balance of spot removal is going to be meta-dependent, though.

[[Shatter the Sky]], [[Pestilent Haze]], sweepers generally: Surprisingly for a creature-based deck, this one might want to run a few sweepers. Between Broodmoth, Orah, and Taborax, our own creatures dying can provide enough value that I think 1-2x sweepers in the maindeck might be correct.