I'm not feeling the here. Looks like a mono- card to me.

@Tahazzar I disagree, but then to me spreading -N/-0 in black is an appropriate expansion o Black's pie.

Well yeah - but it's main blue. So you've got a blue ability; and then another blue ablity that you can activate if you also used black mana.

-5/-1? I guess that's too black?

Black used to have -N/-0, back in the old days: Despondency, Cabal Trainee, Mourning, Torment, Marsh Gas. (It's got occasional recent takes on it with Cast into Darkness and Public Execution. What is with Cast into Darkness anyway? Blue ability + red ability = black card?)

amuseum has their own take on the colour pie, in which black regains this mechanic it used to have. So in that setting, this is a fair hybrid card.

IMO such a (backward) shift in colorpie would be better represented/showcased in a mono- card. Here it's "diluted" when combined with the color that currently has the effect in its pie. I would reserve this kind of hybrid card later on, when the shift has already been given some time to stew for a while (ie. it being more "established").

I find the color pie concerns irrelevant because it's obviously within black. if you can't accept that, that's more your problem and Wizard's incompetence and hesitance to bring the colors together. thus a major flaw of the current color pie.

however vitenka brings up a good point about how to delineate the abilities.

This spell has 3 modes: mono-blue, mono-black, and bicolor. the main effect should fit both monocolor modes. that's fine here. but the bicolor mode is more blue than black.

so the real issue is finding a good ability that blends both blue and black. again not much to work with given the current state of the color pie for and vehement opposition to any remedies for this color pair (as evidenced by the stubbornness in this thread).

a simple (overused) solution is to tack on mill. so:

Hybridize -- If paid both colors, its controller mills 5.

Hmm. Currently share flying, and indeed each have another evasion form, card draw (albeit at a cost for black), both get card filtering, both get back stuff from the grave (black creatures; blue spells) and both share 'control' though by very different mechanical means. There's really surprisingly little mechanical overlap for an ally pair, isn't there.

I'm not completely averse to colour stretching, but a card like this kinda wants to play up the "Hey look, this is both". Or at least have a "This half is more blue, that half is more black" kind of selection.

So you wnt an effect that is but not really . Agony Warp suggests one obvious way to go. -Power in ther either mode, hybridize to -Toughness too?

­Brainbite/Consult the Necrosages/Dimir Guildmage as a different inspiration - always draw a card and discard one; hybrid everyone discards?

­Cemetery Puca suggests both colours can get clone. So make a creature copy P/T and then hybrid give it -3/-3? (Main is more blue, hybrid more black)

Oooh, howabout -n/-0 and hybrid gains flying?

I'm somewhat confused about your stance now, amuseum. On the one hand, you acknowledge that the modern colour pie has a "major flaw" that makes it hard to "bring the colours together", specifically because blue-black are the allied colour pair with the least mechanical overlap and the hardest to design valid hybrid cards for. That's all clearly true and Mark Rosewater has acknowledged it. (They were trying skulk, as on Farbog Revenant/Fogwalker/etc, as a possible new U/B ability, but it didn't work out.)

But then you say that Downsize effects are "obviously within black" and for anyone who doesn't "see" that that's their problem? I don't follow.

The default implicit assumption for all custom card creators is that we're trying to do things similar to what Wizards would do. Most of the time that includes implicitly following the current modern colour pie. (Which is why we get frustrated by the kind of colour pie flaws you've mentioned, and why they're a frequent topic on Maro's blog.) That's not "stubbornness", that's just sticking to the default. But each creator will also have their own areas where they prefer to deviate from Wizards' current standards. Common ones are templating tweaks like "he or she"->"they", allowing higher average complexity because we're mostly not designing for newer players, and certain mechanics that the custom community adopted before Wizards did.

So, amuseum, when you say colour pie concerns are "irrelevant" and "that's your problem", are you saying people should recognise that -N/-0 is within black's current colour pie? Or are you saying it "should" be?

The stubbornness comes from not accepting facts and going by feel.

@Tahazzar: "I'm not feeling the black here. Looks like a mono-blue card to me."

While we have no less than two official hybrid cards that directly provide this ability: Merrow Grimeblotter, Torpor Dust

So the evidence is there to support my argument. But for you designers to ignore that and pretend it as "regressive" and inconceivable is poor judgment and poor vision for the color pie and this color pair in particular.

So if you want to refute me, please provide solid and convincing arguments.

For that matter, past color pie still fall under crust--just less used, but still legitimate. Black has many forms of removal and debuffs. Power debuff being its weakest form is understandably going to be underused unless necessary. Such as debuff auras that want the creature to stick around. per your example Cast into Darkness. Now that's good use of design space, to be flexible rather than stubborn.

There are a multitude of problems with this color pair. Flavorfully they seem to have a unique vast area to share, but mechanically they do things very differently. However reality is their commonality is actual tiny. Even tinier is the subset of abilities that affect creatures, in particular debuffs or negative effects--ironic for a color pair known for control archetype. (Another problem is already occupies many control effects. Unless one is willing to move them to .)

Actually I just found a unique ability for Dimir: (re)move counters and/or auras.

ex.
Hybridize — If blue mana and black mana were spent to cast this spell, remove all counters from that creature.

Much more befitting a spell that debuffs a creature. This would naturally remove +1/+1 counters.

Hmm, removing counters being black and blue? I can see that. Black wants it to clear out its -1 counters it took to cheapen things; and blue just likes messing with mechanics; and already mostlt got it via flickering. Yeah; that works.

"Past colour pie still fall under crust" - Sometimes, yes. There's a bit of a spectrum, from a colour's primary or secondary abilities that are always OK, to tertiary abilities that will be used occasionally, to colour pie crust that's legitimate but unusual, to "acceptable bends" like Form of the Dragon, to more dubious bends like Decimate(1), to outright breaks like Beast Within and Phyrexian Tribute(2). And it's not always clear where along that spectrum something falls. Precedent is obviously not always sufficient, though it's clearly evidence to some extent.

But back on topic, yes, removing counters is an excellent mechanic for U/B. Evokes Fate Transfer, and Leech Bonder, and Vampire Hexmage and Aether Snap.