One thought is having it come with being able to cast them as non-Artifacts if it's done to the furthest extent, allowing for it to be used for some cases of upsides when cast for its minimum cost. This would be referring to the fact that "Completion" is mostly in reference to the merger of flesh and metal of Phyrexians, so a minimum cost would be a creature that isn't Completed at all. Also allows for the presence of good Artifact hate with a lot heavier Artifact backbone than otherwise permissible, as vital deck functions aren't stuck vulnerable to basically all removal.
Of course, much of this could instead be phrased as a Completion keyword that does the opposite of making the creature an Artifact when fully Completed (which is to say cast at highest cost) so CMC inflation doesn't set in, possibly a variant of Level Up that gives parts of the final statline gradually or a subset of Transform that shifts the creature from Mirran to Phyrexian.
Much better, needs a lot of Proliferate to get out of hand with needing three counters, and the smaller mana-fix means the turnaround on investment, which is 1 mana smaller though more flexible, is a lot higher at 6 for 2 instead of 2 for 3, and it can't self-fuel due to the creature spell clause. Still able to Voltron really hard with Bestow, but it takes longer to be doing it routinely, which is the important part for making it more able to be board-wiped as opposed to turn three Chromanticore, made a lot worse if you had another mana dork to get the necessary four mana to Bestow it and land dropped on curve, since you now have a 6/6 Flying First Strike Vigilance Trample Lifelink Hexproof creature on turn 3, ready to go face on turn 4, which spits out a 4/4 that just loses the Hexproof if it gets put down.
As it is now, great Good Stuff creature-commander, perhaps a Superfriends or aggro alternative to Morophon, the Boundless's late-game tribal counterpart, and works perfectly fine in Standard, especially in an environment with less Modern-grade duel-lands to make it less necessary, thanks to needing 6 total mana or a pile of Proliferate invested to get WUBRG. Likely better in the 99 with Jodah, Archmage Eternal, as a way to reliably get the alternate cost going.
Now, time for a repost from The Commander Game:
Mikhal, Forgotten Psyche1W(U/B)(U/B)
Legendary Creature - Specter Wizard
Lifelink, Flying
Whenever Mikhal, Forgotten Psyche deals damage to a player, that player exiles a card in their hand.
Whenever an effect you control would cause an opponent to discard a card, you may pay 2WU and Exile it instead. xWW, Exile a creature in your graveyard with power X or greater: Put an X/X White Thrull creature token with Lifelink into play. xUB: Put an X/X Black Specter creature token with Flying into play with "when this creature enters the battlefield, Exile a Sorcery or Instant you control or in your graveyard with converted mana cost X. Whenever this creature deals combat damage to a player, that player discards a card and you may cast the exiled spell"
3/5 A pale shadow of his former self, but his killers have yet to suspect he hid his self in a lowly thrull.
---
The idea meandered a lot around ways to be Specter Tribal with a reanimation theme, with the flavor text originally being intended to be implemented as a revives-as-Specter mechanic attached to the Thrulls, similar to but slower than Chainer, Dementia Master and in much nicer Commander colors. More specifically, the thought was an Orzhov fleshcrafter killed by a Dimir agent with identity-destroying mind magic, which is where Ravnica Specters come from in general. The flavor text line being that they'd known well enough how to hide away parts of souls, allowing them to avoid total loss of identity in the long run, so they very much know who they used to be... And nobody else does.
Ultimately, I decided to have any revival stuff be a matter of spending 6 mana on a 4/4 Flying Specter that'll cast Blood for Bones or something when it hits the enemy player, allowing for other spells if desired, but also being decidedly easier to stop since you could kill the specter, keep blocking it, counter the recast spell or whatever. Also means you're able to creature-flood in Esper Control, I suppose, though you have to match your spell costs and throw on two more mana. Adds a lot of extra timing complexity since the spells come out after damage is assigned, which is important for preventing the combat tricks from swinging things massively on a regular basis.
Burning BogspawnBRG
Creature - Elemental Nightmare
Burning Bogspawn gets +1/+1 for each Swamp you control.
Whenever a Forest enters the graveyard, Burning Bogspawn gains Trample and +0/+2
Whenever a Mountain enters the battlefield, Burning Bogspawn gains First Strike and +2/+0
1/2
For an example of the "Kill My Things" deck type, here's a video of one in the proper colors. Dreadhorde Butcher is a pretty big target to make an argument for Abnormal Endurance over Unlikely Aid, especially alongside Midnight Reaper turning the repeated deaths into cards drawn (also done by so that the rates of reaching the engines is increased significantly.
I don't keep track of the game with nearly enough detail to be able to spin off a decklist with any kind of ease, I just know what mechanics at large exist and can look at cards and pretty quickly think of what could go well with them. Actually fitting the pieces together? Takes a rather long time for me to even try to get started on that.
So I can point out that Costly Plunder and Blood Divination are good for digging through the deck to reach Feather so recurring the draw-upside cards can begin, but I don't actually know how to run all the numbers to determine which card with this sort of effect is best, or whether it's worth the deck space taken away from a cantrip that does something else in addition to drawing a card, or if the death triggers as a whole can make them viable over the draw-and-also-something cards. Heck, given the idea of having the deck be mostly Reanimator with a splash of White for Feather to recur some stuff, Ajani's Influence as a four-of and Feather and Teysa Karlov as less-than four-ofs could work out perfectly well, burrowing through the deck for the few White cards of importance while building up a Dreadhorde Butcher to burn the enemy down or off a Planeswalker.
Basically, I know what the numbers are, but don't know how to crunch them, because I have issues with keeping track of the number of variables that go into making a whole deck function smoothly, so I have to build out decks one card interaction at a time more or less by feel.
The idea of a three-mana gain for creature spells is a bit dangerous, and the easy production of WUBRG means that a mostly-Golgari deck can get quickly out of hand with creatures like Chromanticore or Child of Alara. Setting aside the cheese of return-to-hand mixing with WUBRG generation, Hexproof makes this thing generally nasty with Bestow as a whole, letting you reliably cast Bestow in every color, especially Kestia, the Cultivator.
Basically, I think it's too powerful a color-fixer and ramper to excuse the presence of Hexproof when it obviously permits a deck full of powerful buffs, as it pays for itself the turn its out if you get it Haste and can spend the mana.
---
Opaline Umbra1W
Enchantment - Aura
Enchant non-Aura Enchantment
Enchanted Enchantment becomes a White Creature with power and toughness equal to its converted mana cost, in addition to its other colors and types.
Totem Armor
---
The initial thought is simple: Single-target Opalescence as an Umbra. Can protect the enchantment from a piece of removal, and some high-cost Enchantments become good creatures. Can be used to bypass Devotion requirements on Gods, as well as set statlines on other Enchantment Creatures. The non-Aura clause is because of rules issues and my main thought for solving them being giving Bestow, which makes them sticky, sometimes beyond reason, and if they self-enchant and get the CMC P/T, then stuff like Yavimaya's Embrace turn into utterly absurd value swings. +10/+10, trample and creature stealing for 8? Turning into a 10/10 trampler when the stolen creature dies? The complexity of fixing that mess of interactions would need to be a card dedicated to that idea alone.
Unfortunately, most of the cards you listed just don't work for Feather.
Abnormal Endurance is okay, but Unlikely Aid is better. During an combat phase your creatures hit. Bladebrand is inferior to Defiant Strike. If you want deathtouch, that means you're attacking into bigger threats, which means yor attacker is likely to die. Feather doesn't want targets to die. Bleeding Edge is ok, but 3 cmc is too high. You would have to choose from casting this or another card more often than not. Fungal Infection is much more playable, but still not that impressive. Clear the Stage way too costly and situational. Blessing of Belzenlok is solid. Nightmare's Thirst and Skulduggery are just bad, the former could only work in a dedicated deck. Macabre Mockery doesn't work, creature card in a graveyard is not the same as creature you control Undercity Uprising is so much worse than Prey Upon...
Well, overall not yet there.
Doesn't work for the [i]existing[/i] Feather strategies. The idea is actually more splashing white into a mostly-Black strategy for Feather to recur some valuable effects in a different kind of creature-based strategy, rather than being [i]primarily[/i] a large pile of combat tricks like the current Feather strategies.
The reason I brought up Macabre Mockery is that the creature [i]is[/i] on the field and affected by the card, so you [i]do[/i] control it as the card affects it on the battlefield. I'm not sure if the attached buff, which is a separate clause, counts for Feather's targeting requirement. It's very much an edge case mentioned because of the [i]chance[i] of recurrent reanimation.
Skulduggery is a 2/2 swing for one mana and will [i]always[/i] recur with Feather. If two of them are in hand, everything with two toughness is a valid target for recurring two-mana removal. Nightmare's Thirst pairs perfectly well with Blessing of Belzenlok for a reliable -6/-6 when you eventually need it (and with M20 coming up, it'd fit well for an Orzhov-base lifegain deck splashing red for Feather) and being a life a turn for a mana whenever you have Black spare before that, while Undercity Uprising is mentioned for the "all creatures you control gain Deathtouch" as a way to crack open the board and close out the game, the Fight trigger is just why it recurs to [i]keep[/i] cracking the board open until they can't keep blocking. You only need one of it, as it's there to be a win condition when you eventually come across it in longer games, and you have Black for [i]much[/i] harder removal than Prey Upon.
Abnormal Endurance has the important potential advantage of allowing creatures to leave the battlefield, letting both ETB and on-death effects trigger in the process, while Unlikely Aid is only better if you're wanting to smash the opposing line. In which case, you've got reanimation because you're running Black, just use Bladebrand and bring the thing whatever they used the big threat to block back, if you actually care about it enough. Bladebrand is far better as a combat trick, since it [i]outright kills[/i] most blocking creatures instead of only swinging by 1 power. Yes, it costs one more. It's also pretty close to recurrent removal for two, in this case, and there's no reason you can't run two of it and two of Defiant Strike, or some other ratio to smooth draw power and color distribution.
Essentially, the idea is altering a "Kill My Things" deck or some Reanimator strategy into a Feather deck, running removal-with-upside to trigger the deaths and having Feather recur this self-targeted removal to [i]keep[/i] triggering it as desired while preserving the removal for if you need to hit an enemy with it, with combat tricks so you can close out with combat easier and handle other creature-based decks, rather than having the combat tricks be the only engine of the deck's strategy.
I don't really have an exact decklist in mind, just a general deck idea for Mardu-colored Feather.
It also has a bit of a deckbuilding advantage over the venerable Assault Loam combo: It's triple-colored in its cost in the same color as Life from the Loam, so you can be comfortably monocolored.
Thanks to Gaea's Blessing, you don't even have to worry about decking out, and can (potentially) reclaim vital deck components whenever they get Dredged into the graveyard.
Renegade Watchwing2WR
Creature - Angel Rebel
Fabricate 3, Flying, Riot
Remove a +1/+1 counter from Renegade Watchwing: It Fights target blocked or blocking creature. RB: Monstrosity 3.
While Renegade Watchwing is Monstrous, it is a Black Artifact Aetherborn in addition to its other colors and types and has "at the beginning of each upkeep, put a -1/-1 counter on Renegade Watchwing and you gain E" and "E: Renegade Watchwing gains Lifelink and is a Vampire in addition to its other types until end of turn"
0/2
---
IIW: Take a creature type focused on a mechanic, then twist that mechanic. Like an ability-taking Sliver, or a Blue/White Nightmares with Oblivion Ring effects in reference to but deviating from the Wormfang ones. Or, say, Black Rebels that tutor down through the graveyard. Stuff like that...
To touch on the Mardu variant, Abnormal Endurance seems a rather major effect, and Bladebrand is a key source of card advantage. If you can somehow reliably have enough Toughness to withstand it, Bleeding Edge can be a good Amass generator, with Clear the Stage being a similar recurrent upside for using a debuff on your own stuff. Blessing of Belzenlok is very good for Feather herself, giving a steady stream of life at a low cost that also gives a bit of a buffer from damage, and combos a bit with Nightmare's Thirst. A pretty big bit of power would be Skulduggery, as it'll turn into recurrent removal with relatively few of them.
The biggest Rakdos card I see that probably works is Macabre Mockery, if revival as a whole doesn't count, and if revival as a whole does count, it becomes an extremely powerful Reanimator recursion deck. Angrath's Fury, if you can get enough revival for the destruction, becomes a stupid bit of Planeswalker recursion, if you're that desperate for Angrath... For some reason. If you can somehow get reliable access to one green mana, Undercity Uprising closes out the game hard, and Status // Statue gives single-target Deathtouch without needing green and becomes extremely flexible removal when you have a bit of Green mana. If green were in the base, then such single-mana inclusions for win conditions or answers would be a lot easier, as you could semi-reliably fetch the relevant basic land as a one-or-two-of.
I can see a Reanimator sort of aggro-control setup splashing White for Feather recurring normally-detrimental effects for their riders.
There's two things Ayula's Influence does: It gives you creatures independently of mana, and it's an outlet for mana flooding. These are quite at odds, but, with the amount of tutor-based ramp in the game, it can actually be used quite well in a few different creature-based decks, so long as they can get the mana to cast it reliably, which the tutor-based draw does quite effectively by fetching the minimum necessary Forests.
The advantage over Zombie Infestation is that it ties in well with a major form of card draw in its color, while Black has often-limited draw power, needing to intersect with other colors to power its own draw engines or otherwise being reliant on more fragile combos to fuel it.
Wormfang Sphinx2(W/U)(W/U)
Creature - Nightmare Sphinx
When Wormfang Sphinx enters the battlefield, fateseal 3, then exile the top card of your deck. (To fateseal 3, look at the top three cards of an opponent's library, then put any number of them on the bottom of that player's library and the rest on top in any order.)
When Wormfang Sphinx leaves the battlefield, return the exiled card to the top of its owners deck.
3/4
---
The reason it's either is that the Wormfang mechanic is actually re-identified to White, through cards like Oblivion Ring, and there's some White scrying in the game. So the mechanic could work in either color.
Mikhal, Forgotten Psyche1W(U/B)(U/B)
Legendary Creature - Specter Wizard
Lifelink, Flying
Whenever Mikhal, Forgotten Psyche deals damage to a player, that player exiles a card in their hand.
Whenever an effect you control would cause an opponent to discard a card, you may pay 2WU and Exile it instead. xWW, Exile a creature in your graveyard with power X or greater: Put an X/X White Thrull creature token with Lifelink into play. xUB: Put an X/X Black Specter creature token with Flying into play with "when this creature enters the battlefield, Exile a Sorcery or Instant you control or in your graveyard with converted mana cost X. Whenever this creature deals combat damage to a player, that player discards a card and you may cast the exiled spell"
3/5 A pale shadow of his former self, but his killers have yet to suspect he hid his self in a lowly thrull.
---
Next: A Commander that supports a combo of Graft and board-flooding reanimation. Can be reanimation and Proliferate with green and/or blue in the color identity to acquire Graft externally to the commander, or be rooted in Scavenge assistance that floods the board so that it loads up the Graft creatures with enough counters to get one on all the creatures in the flood. Doesn't need to directly be Graft and high-creature-count Reanimation on the Commander itself.
Kraj, Mycosic OmnidisciplinaryxBGGU
Legendary Creature - Fungus Ooze Mutant
Graft 2
Kraj, Mycosic Omnidisciplinary comes into play with a number of +1/+1 counters equal to the mana spent to cast it. WB, : Exile target creature from a graveyard. Put a White Zombie creature token with Power and Toughness equal to the exiled creature's into play. Kraj, Mycosic Omnidisciplinary gains the abilities of the exiled creature while that token remains in play. UR, : Counter or copy target activated or triggered ability, then put a Red Elemental creature token with power and toughness equal to the mana spent on the ability countered. Kraj, Mycosic Omnidisciplinary gains the target ability while that token remains in play.
---
Next: A three-color commander that supports at least one keyword of each Ravnica Guild in its colors, as well as the mechanic of the Alara Shard or Tarkir Clan. So, for example, a Bant-colored one would have to support Exalted from Bant, Populate or Convoke from Selesnya, Forecast, Addendum or Detain from Azorius, and Graft, Evolve or Adapt from Simic.
Raid-Mob Seditionist1R
Creature - Goblin Coward
Whenever you cast your Commander from somewhere other than the Command zone, you may pay mana as if you had. If you do, put a +1/+1 counter on another target creature for each Red mana spent above your Commander's converted mana cost and deal that much damage to Raid-Mob Seditionist.
Of course, much of this could instead be phrased as a Completion keyword that does the opposite of making the creature an Artifact when fully Completed (which is to say cast at highest cost) so CMC inflation doesn't set in, possibly a variant of Level Up that gives parts of the final statline gradually or a subset of Transform that shifts the creature from Mirran to Phyrexian.
Also, it's spelled "Incomplete".
As it is now, great Good Stuff creature-commander, perhaps a Superfriends or aggro alternative to Morophon, the Boundless's late-game tribal counterpart, and works perfectly fine in Standard, especially in an environment with less Modern-grade duel-lands to make it less necessary, thanks to needing 6 total mana or a pile of Proliferate invested to get WUBRG. Likely better in the 99 with Jodah, Archmage Eternal, as a way to reliably get the alternate cost going.
Now, time for a repost from The Commander Game:
Mikhal, Forgotten Psyche 1W(U/B)(U/B)
Legendary Creature - Specter Wizard
Lifelink, Flying
Whenever Mikhal, Forgotten Psyche deals damage to a player, that player exiles a card in their hand.
Whenever an effect you control would cause an opponent to discard a card, you may pay 2WU and Exile it instead.
xWW, Exile a creature in your graveyard with power X or greater: Put an X/X White Thrull creature token with Lifelink into play.
xUB: Put an X/X Black Specter creature token with Flying into play with "when this creature enters the battlefield, Exile a Sorcery or Instant you control or in your graveyard with converted mana cost X. Whenever this creature deals combat damage to a player, that player discards a card and you may cast the exiled spell"
3/5
A pale shadow of his former self, but his killers have yet to suspect he hid his self in a lowly thrull.
---
The idea meandered a lot around ways to be Specter Tribal with a reanimation theme, with the flavor text originally being intended to be implemented as a revives-as-Specter mechanic attached to the Thrulls, similar to but slower than Chainer, Dementia Master and in much nicer Commander colors. More specifically, the thought was an Orzhov fleshcrafter killed by a Dimir agent with identity-destroying mind magic, which is where Ravnica Specters come from in general. The flavor text line being that they'd known well enough how to hide away parts of souls, allowing them to avoid total loss of identity in the long run, so they very much know who they used to be... And nobody else does.
Ultimately, I decided to have any revival stuff be a matter of spending 6 mana on a 4/4 Flying Specter that'll cast Blood for Bones or something when it hits the enemy player, allowing for other spells if desired, but also being decidedly easier to stop since you could kill the specter, keep blocking it, counter the recast spell or whatever. Also means you're able to creature-flood in Esper Control, I suppose, though you have to match your spell costs and throw on two more mana. Adds a lot of extra timing complexity since the spells come out after damage is assigned, which is important for preventing the combat tricks from swinging things massively on a regular basis.
Creature - Elemental Nightmare
Burning Bogspawn gets +1/+1 for each Swamp you control.
Whenever a Forest enters the graveyard, Burning Bogspawn gains Trample and +0/+2
Whenever a Mountain enters the battlefield, Burning Bogspawn gains First Strike and +2/+0
1/2
---
Next: Kykar, Wind's Fury
Went ahead and quickly looked up the sort of deck I was thinking of diverging from, and found somebody else's Mardu Feather decklist that splashes black for control and Sorin, Vengeful Bloodlord, with a video going over it on Arena.
For an example of the "Kill My Things" deck type, here's a video of one in the proper colors. Dreadhorde Butcher is a pretty big target to make an argument for Abnormal Endurance over Unlikely Aid, especially alongside Midnight Reaper turning the repeated deaths into cards drawn (also done by so that the rates of reaching the engines is increased significantly.
I don't keep track of the game with nearly enough detail to be able to spin off a decklist with any kind of ease, I just know what mechanics at large exist and can look at cards and pretty quickly think of what could go well with them. Actually fitting the pieces together? Takes a rather long time for me to even try to get started on that.
So I can point out that Costly Plunder and Blood Divination are good for digging through the deck to reach Feather so recurring the draw-upside cards can begin, but I don't actually know how to run all the numbers to determine which card with this sort of effect is best, or whether it's worth the deck space taken away from a cantrip that does something else in addition to drawing a card, or if the death triggers as a whole can make them viable over the draw-and-also-something cards. Heck, given the idea of having the deck be mostly Reanimator with a splash of White for Feather to recur some stuff, Ajani's Influence as a four-of and Feather and Teysa Karlov as less-than four-ofs could work out perfectly well, burrowing through the deck for the few White cards of importance while building up a Dreadhorde Butcher to burn the enemy down or off a Planeswalker.
Basically, I know what the numbers are, but don't know how to crunch them, because I have issues with keeping track of the number of variables that go into making a whole deck function smoothly, so I have to build out decks one card interaction at a time more or less by feel.
Basically, I think it's too powerful a color-fixer and ramper to excuse the presence of Hexproof when it obviously permits a deck full of powerful buffs, as it pays for itself the turn its out if you get it Haste and can spend the mana.
---
Opaline Umbra 1W
Enchantment - Aura
Enchant non-Aura Enchantment
Enchanted Enchantment becomes a White Creature with power and toughness equal to its converted mana cost, in addition to its other colors and types.
Totem Armor
---
The initial thought is simple: Single-target Opalescence as an Umbra. Can protect the enchantment from a piece of removal, and some high-cost Enchantments become good creatures. Can be used to bypass Devotion requirements on Gods, as well as set statlines on other Enchantment Creatures. The non-Aura clause is because of rules issues and my main thought for solving them being giving Bestow, which makes them sticky, sometimes beyond reason, and if they self-enchant and get the CMC P/T, then stuff like Yavimaya's Embrace turn into utterly absurd value swings. +10/+10, trample and creature stealing for 8? Turning into a 10/10 trampler when the stolen creature dies? The complexity of fixing that mess of interactions would need to be a card dedicated to that idea alone.
Doesn't work for the [i]existing[/i] Feather strategies. The idea is actually more splashing white into a mostly-Black strategy for Feather to recur some valuable effects in a different kind of creature-based strategy, rather than being [i]primarily[/i] a large pile of combat tricks like the current Feather strategies.
The reason I brought up Macabre Mockery is that the creature [i]is[/i] on the field and affected by the card, so you [i]do[/i] control it as the card affects it on the battlefield. I'm not sure if the attached buff, which is a separate clause, counts for Feather's targeting requirement. It's very much an edge case mentioned because of the [i]chance[i] of recurrent reanimation.
Skulduggery is a 2/2 swing for one mana and will [i]always[/i] recur with Feather. If two of them are in hand, everything with two toughness is a valid target for recurring two-mana removal. Nightmare's Thirst pairs perfectly well with Blessing of Belzenlok for a reliable -6/-6 when you eventually need it (and with M20 coming up, it'd fit well for an Orzhov-base lifegain deck splashing red for Feather) and being a life a turn for a mana whenever you have Black spare before that, while Undercity Uprising is mentioned for the "all creatures you control gain Deathtouch" as a way to crack open the board and close out the game, the Fight trigger is just why it recurs to [i]keep[/i] cracking the board open until they can't keep blocking. You only need one of it, as it's there to be a win condition when you eventually come across it in longer games, and you have Black for [i]much[/i] harder removal than Prey Upon.
Abnormal Endurance has the important potential advantage of allowing creatures to leave the battlefield, letting both ETB and on-death effects trigger in the process, while Unlikely Aid is only better if you're wanting to smash the opposing line. In which case, you've got reanimation because you're running Black, just use Bladebrand and bring the thing whatever they used the big threat to block back, if you actually care about it enough. Bladebrand is far better as a combat trick, since it [i]outright kills[/i] most blocking creatures instead of only swinging by 1 power. Yes, it costs one more. It's also pretty close to recurrent removal for two, in this case, and there's no reason you can't run two of it and two of Defiant Strike, or some other ratio to smooth draw power and color distribution.
Essentially, the idea is altering a "Kill My Things" deck or some Reanimator strategy into a Feather deck, running removal-with-upside to trigger the deaths and having Feather recur this self-targeted removal to [i]keep[/i] triggering it as desired while preserving the removal for if you need to hit an enemy with it, with combat tricks so you can close out with combat easier and handle other creature-based decks, rather than having the combat tricks be the only engine of the deck's strategy.
I don't really have an exact decklist in mind, just a general deck idea for Mardu-colored Feather.
Thanks to Gaea's Blessing, you don't even have to worry about decking out, and can (potentially) reclaim vital deck components whenever they get Dredged into the graveyard.
Creature - Angel Rebel
Fabricate 3, Flying, Riot
Remove a +1/+1 counter from Renegade Watchwing: It Fights target blocked or blocking creature.
RB: Monstrosity 3.
While Renegade Watchwing is Monstrous, it is a Black Artifact Aetherborn in addition to its other colors and types and has "at the beginning of each upkeep, put a -1/-1 counter on Renegade Watchwing and you gain E" and "E: Renegade Watchwing gains Lifelink and is a Vampire in addition to its other types until end of turn"
0/2
---
IIW: Take a creature type focused on a mechanic, then twist that mechanic. Like an ability-taking Sliver, or a Blue/White Nightmares with Oblivion Ring effects in reference to but deviating from the Wormfang ones. Or, say, Black Rebels that tutor down through the graveyard. Stuff like that...
The biggest Rakdos card I see that probably works is Macabre Mockery, if revival as a whole doesn't count, and if revival as a whole does count, it becomes an extremely powerful Reanimator recursion deck. Angrath's Fury, if you can get enough revival for the destruction, becomes a stupid bit of Planeswalker recursion, if you're that desperate for Angrath... For some reason. If you can somehow get reliable access to one green mana, Undercity Uprising closes out the game hard, and Status // Statue gives single-target Deathtouch without needing green and becomes extremely flexible removal when you have a bit of Green mana. If green were in the base, then such single-mana inclusions for win conditions or answers would be a lot easier, as you could semi-reliably fetch the relevant basic land as a one-or-two-of.
I can see a Reanimator sort of aggro-control setup splashing White for Feather recurring normally-detrimental effects for their riders.
The advantage over Zombie Infestation is that it ties in well with a major form of card draw in its color, while Black has often-limited draw power, needing to intersect with other colors to power its own draw engines or otherwise being reliant on more fragile combos to fuel it.
Creature - Nightmare Sphinx
When Wormfang Sphinx enters the battlefield, fateseal 3, then exile the top card of your deck. (To fateseal 3, look at the top three cards of an opponent's library, then put any number of them on the bottom of that player's library and the rest on top in any order.)
When Wormfang Sphinx leaves the battlefield, return the exiled card to the top of its owners deck.
3/4
---
The reason it's either is that the Wormfang mechanic is actually re-identified to White, through cards like Oblivion Ring, and there's some White scrying in the game. So the mechanic could work in either color.
Next: Zur the Enchanter
Legendary Creature - Specter Wizard
Lifelink, Flying
Whenever Mikhal, Forgotten Psyche deals damage to a player, that player exiles a card in their hand.
Whenever an effect you control would cause an opponent to discard a card, you may pay 2WU and Exile it instead.
xWW, Exile a creature in your graveyard with power X or greater: Put an X/X White Thrull creature token with Lifelink into play.
xUB: Put an X/X Black Specter creature token with Flying into play with "when this creature enters the battlefield, Exile a Sorcery or Instant you control or in your graveyard with converted mana cost X. Whenever this creature deals combat damage to a player, that player discards a card and you may cast the exiled spell"
3/5
A pale shadow of his former self, but his killers have yet to suspect he hid his self in a lowly thrull.
---
Next: A Commander that supports a combo of Graft and board-flooding reanimation. Can be reanimation and Proliferate with green and/or blue in the color identity to acquire Graft externally to the commander, or be rooted in Scavenge assistance that floods the board so that it loads up the Graft creatures with enough counters to get one on all the creatures in the flood. Doesn't need to directly be Graft and high-creature-count Reanimation on the Commander itself.
Legendary Creature - Fungus Ooze Mutant
Graft 2
Kraj, Mycosic Omnidisciplinary comes into play with a number of +1/+1 counters equal to the mana spent to cast it.
WB,
UR,
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Next: A three-color commander that supports at least one keyword of each Ravnica Guild in its colors, as well as the mechanic of the Alara Shard or Tarkir Clan. So, for example, a Bant-colored one would have to support Exalted from Bant, Populate or Convoke from Selesnya, Forecast, Addendum or Detain from Azorius, and Graft, Evolve or Adapt from Simic.
Creature - Goblin Coward
Whenever you cast your Commander from somewhere other than the Command zone, you may pay mana as if you had. If you do, put a +1/+1 counter on another target creature for each Red mana spent above your Commander's converted mana cost and deal that much damage to Raid-Mob Seditionist.
1/3
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Next: Haakon, Stromgald Scourge
Creature - Goblin Shaman
Whenever another non-token Goblin creature enters the graveyard, you may choose one:
- Put a 1/1 Red Goblin creature token onto the battlefield
- Add R to your mana pool
- Deal 1 damage to target creature
2/4---
Note: this includes discard and mill, since it doesn't specify from the battlefield.
Next: Doran, the Siege Tower