Magic The Gathering

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Black cards

Coronation of the God-King: - :(N/A)
Legendary Sorcery
Coronation of the God-King is both black and white, and cannot not be black and white.
Coronation of the God-King cannot enter play if your devotion to black is greater than your devotion to white.
Suspend 20 - 3 white, tap all your white nonland permanents.
Madness 3 black, sacrifice any number of non-artifact creatures with a total of 30 toughness
When Coronation of the God-King enters play, exile 3 lands you control. You then have the following Emblem:
tap: Play any card, with a converted mana cost of 3 or less from your hand, or with a converted mana cost of 2 or less from your graveyard, as an instant.
you may untap the emblem whenever you would untap a land.
"The people of the land loved their domain enough to eagerly bleed at the pleasure of its sovereign."

Basilisk, King of Serpents: three green, five black :(8)
Legendary Enchantment Creature, Snake Horror 5/7
As an additional cost, sacrifice a land and a creature you control.
Menace, Trample, Deathtouch, Double Strike
X black, X = number of creatures, tap: Enchant any number of untapped target creatures with Petrification: enchanted creature loses all abilities, becomes a 0/4 artifact creature that can't attack or block, and gains the ability: during your upkeep, tap creatures you control up to your devotion to any one color, and exile all Petrifications attached to tapped creatures you control.

Perfect Ecosystem: three black, two green :(5)
Enchantment
Choose a type of basic land.
All nonbasic land you control with that land type, or describing land of that type, are basic. (a land describes a type if its artwork or name indicates the type, consult a dictionary if necessary.)
or
Choose a color.
All nonbasic land you control of that color are basic.
"These sorts of terrain are common enough from where I'm from."

Nature's Perfection: three black, three green :(6)
Enchantment
You may play this card for one less mana for every three qualities among permanents you control, to a min. of (0). If you play it for (0), also suspend 2.
Other permanents you control only count as any one of their qualities as beneficial. (a White/Black creature would ignore protection white or protection black; needing both to be affected.)
"Natural choice exalts diversity where your magic would cull it."

Concordant Darkness: four mana, one black or two life, one green, one white:(7)
Enchantment
Play this card for one mana less (to a min. of 1) for each black card with a drawback or downside in your hand or control.
Black creatures you own do not have drawbacks or downsides, unless the creature has a converted mana cost less than half of the sum of its power and toughness plus one for every two and more keyword abilities and strictly beneficial non-keyword abilities.
You may choose not to apply this enchantment to any card at any time.
At the beginning of your untap step, any opponent may pay one black, 2 life, sacrifice a creature, or discard a card. If a player does, you lose the benefit of this card and shuffle it back into your library.
"Black mana is the source of our power, not the master of our strength."

Fair Barter: four mana, one black or two life, one blue, one red :(7)
Enchantment
Play this card for one mana less (to a min. of 1) for each time you've lost life, sacrificed a permanent, or discarded a card by your own actions.
Whenever a black card you own calls for you to lose life, sacrifice a permanent, or discard a card, examine it. If there is a sorcery, an instant, an enchantment, or an ability of another color that creates an equivalent or better effect for as much or less mana, the card does not call for any of the listed. Creature cards that call for any of the listed cost one mana less for every two life, every one sacrifice, or every one discard each. Otherwise play the card normally.
At the beginning of your untap step, any opponent may pay one black, 2 life, sacrifice a creature, or discard a card. If a player does, you lose the benefit of this card and shuffle it back into your library.
"Expense for the sake of expense is the very antithesis of power."

Pact Warlock: two mana, three black :(5)
Enchantment
Pact Warlock is indestructible as long as you control a black creature or artifact.
Black creatures and artifacts you play from your hand can't be countered.
"The pact-bound are slaves to their binders, and must obey even at expense to themselves."

Fel Warlock: two mana, three black :(5)
Enchantment
This card cannot be countered.
When Fel Warlock would leave the battlefield all players lose life equal to your devotion to black.
Black instants, sorceries, and enchantments you play can't be countered unless the opponent pays X life where X is your devotion to black.
""Quench this!"- some warlock before lobbing two gallons of volatile demonic energy at a blue mage."

Necromancers' Fair: four black :(4)
Enchantment
Whenever a creature you control would enter a graveyard, exile it instead. Whenever you do, you may suspend X - 0, where X is its converted mana cost, but place the creature into your graveyard instead of play.
Whenever any non-artifact creature would enter any graveyard, create a black corpse token artifact with the ability to tap, sacrifice corpse: add one black only for casting a zombie card.
""Just because you used the body while alive-" an irate necromancer defending their craft"

Surface Corruption: 3 black :(3)
Enchantment
tap, pay X black: play a nonblack card for its normal mana cost, only replacing any mana of another color with black. X equals the number of distinct mana markers featured in that card's mana cost. (generic, any color, snow, phyrexian colors, hybrids...)
"A barrel of sewage with a thimble of wine is sewage, the opposite is also sewage. Think about what that means regarding magic."

Shadelink: one black :(1) / variant bloodlink for ooze tokens
Enchantment
Whenever you lose life as the result of a card you own, place X 1/1 shade token creatures on the battlefield, where X is the amount of life you lost -1.
If you would lose life as the result of mana burn, you may place X 2/2 shade token creatures on the battlefield, where X is the amount of life you would lose. If you do, tap half of the lands that caused your mana burn. You may also do this when a static effect imitates mana burn for you.
one black, tap: Sacrifice any X shade token creatures and place a single X/X shade token creature with fear where X is the amount of life you lost last.
"All too often does power come at a price, best ensure its worth to pay it."

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Black is the mana of power and seeking it in all its forms, the mana of reaching any ambitions you desire in any way you please. As such it is understandable that black can do a lot of things other colors do, but what is strange is how much more expensive it tends to be.
The flavor of black is described as playing easymode to dark souls, everyone else is restricted in what they can do and having a hard time at it, but black doesn't give a shit. Instead the first impression flavor of black cards tends to be to waste as much resources as possible because 'it's black hur dur I'm so edgy'.
White makes it easier to cooperate and persuade large groups at once, green makes it easy to focus on living and helps you keep at it, red makes you enjoy life and is all-fuck-powerful, blue keeps your mind at its best and your head cool, but black apparently makes you lose all sense of economics, foresight, and internal growth.

Sacrifice a permanent or discard a card are at best worth zero mana, and costs at worst an arbitrary large amount. In general I like to think of both of these as apply one mana more in the form of a sacrifice.

Phyrexian mana set up an elegant system where 2 life is worth one mana, which some of the above draws from. Then again Lightning Bolt is a one red instant worth 3 life, and several black cards toll you for 1 life as they do things... In general one mana is worth 2 life, and a card or tapping one is worth 1 life. Lightning Bolt, 1 mana / 2 life, + one card / 1 life, = 3 damage. Ancestral Recall, 1 mana / 2 life, + one card / 1 life, = draw 3. In general red is the only color that can transform mana into damage this well, blue mana to card advantage, green mana to enhancement, white mana to healing, and black mana to diminishment.

Cards like Un/Holy Strength and their strictly better variants like Deviant Glee and Predator's Gambit also show that a card +one mana is worth about +2/+2 on a creature, and that keyword abilities are worth about +1/0 or 0/+1 can be gleaned from various one mana 1/1 flying (or something else) cards. In general every +1/+1 is worth 1 life, and every keyword ability is worth 1 life (one half unit mana).

In creatures a 0 mana card seems to pay for any three of the following perks: a 0/1 creature and *, + a non-/keyword ability and *, + one mana ability and *, +1 to power or toughness and *at least 1 drawback or downside on the card*. Each additional drawback or downside lets you pick an additional perk, and taking only two perks counts as a downside. A +1 (any) mana cost counts as a drawback, and a each color of mana in cost after the first counts as two. A -1 to either power or toughness counts as a downside, and a zero on either one counts as two. Some abilities are greater than others, and thus require additional drawbacks, some drawback and downsides are worse than others, and thus count as two. Summoning sickness is not considered a drawback on creatures that require less than three mana, this increases the worth of expensive cards.

Best part about turning anything mtg into a narrative based format is adjusting the value of one mana, and tapping a permanent to make sense without turns or card advantage. Also consider the game-only limitations on hand size and libraries, if graveyard exist at all, and what needs be done to attune a land.

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silverborder cards, meant for fun and flavor rather than the game itself

Grim Darkness: three black :(3)
Enchantment
protection from nonblack
All effects that cause any amount power/toughness reduction are permanent. Use -1/-1 counters if you can't keep count without them.
"If you fail to maintain a severe, grim, stoic façade, exile this card into its own zone which is as far as you can throw it."

Imbue Periapt: two black :(3)
Enchantment Artifact
tap, X: Enchant creature where X is equal to the colored mana cost of that creature. Create a black amulet token aura artifact with indestructible and the ability:
when you next play a card of the same name after enchanted creature has died, you may tap, sacrifice amulet: target creature with the name of the enchanted creature you controlled gains all beneficial permanent spell effects that enchanted creature had before it died. (gains the effects of all beneficial auras it had, benefits from all counters it bore, effects other creatures gave it, etc.)
"Started as below did, meant to evoke the flawless recreation of a specific creature. Yes that beneficial enchantment part includes Imbue Periapt."

Fragile Phylactery: two black :(2)
Artifact Enchantment
Equip (2)
As long as Fragile Phylactery is in play and has not been equipped again, last equipped creature has unearth: sacrifice Fragile Phylactery.
Alternatively, As long as Fragile Phylactery is equipped, it has a toughness score equal to the equipped creature, takes any damage in place of the equipped creature, and redirects any effect that would destroy equipped the creature unto itself.
"World of Warcraft Soulstone interpretation for mtg universe."

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Unholy Strength fix
+ Enchanted creature has protection fog each combat after your turn it did not block in. (combat damage dealt by this creature cannot be prevented by effects that say all damage.)

Holy Strength fix
+ Enchanted creature has protection first strike each combat after your turn it did not attack in. (this creature does not receive first strike damage.)