Cards like Judge's Familiar and other hybrid-colored cards should not change the color of the deck on their own. For instance, I have a G/W deck without a Judge's Familiar, but when I add the Judge's Familiar it becomes a G/W/U deck, which is inaccurate as there is never a situation in which I will use blue mana to cast the card.

Hybrid cards should either (a) not have any influence on deck color (similar to artifacts) or (b) influence deck color smartly; i.e. only influence deck color if neither of the card's colors is already represented in the deck.

That's very relative because in a format like EDH it does affect the colors, using your example if you're using a Green White commander you can't use Judge's Familiar, also the same argument could be made for reanimator decks that can't physically cast some of their bombs so that card's color shouldn't be part of the deck's colors yet it is anyway.

It might be better to have a manual override for color, and perhaps format as well. Maybe with a warning icon on the deck page to let you know just in case you do change colors and forget to set them back.

Doesn't it stem from Wizards' long-standing view that a card with dual mana options is automatically considered both colors. Thus, with Judge's Familiar, the card is both a Blue Card and a White Card simultaneously. Either Protection from White or Protection from Blue would prevent damage or effects based on that card. You may only be casting it using one of its possible colors, but effects that center on the other color would still be valid.

HikingStick wrote:Doesn't it stem from Wizards' long-standing view that a card with dual mana options is automatically considered both colors. Thus, with Judge's Familiar, the card is both a Blue Card and a White Card simultaneously. Either Protection from White or Protection from Blue would prevent damage or effects based on that card. You may only be casting it using one of its possible colors, but effects that center on the other color would still be valid.

I have no problem with the fact that the card is considered both colors, I just don't think a deck should be considered tri-color just because it has one measly hybrid card in it. For all intents and purposes I'm playing a green/white deck. I call it a green/white deck, my friends call it a green/white deck, any reasonable Magic player who looks at it will say "That's a green/white deck". I think deckbox's color designation should not call it tri-color based on a technicality.

varble wrote:It might be better to have a manual override for color, and perhaps format as well. Maybe with a warning icon on the deck page to let you know just in case you do change colors and forget to set them back.

I like this option personally. It seems like this could add in a whole new option of searching in the future as well. You could see what people have flagged as a standard G/W deck or a commander R/U/G deck, even if that commander deck currently has 101 cards so Deckbox thinks it's just a funky legacy deck.

So, would it be better for the deck color to be based on the color of mana sources in the deck, rather than on the cards that are cast? In that case, however, we end up with the same scenario if someone is using a dual land for the wow factor, but has no intention of tapping for the second land color.

In the overall scheme of things, how important is that designation? If you know the deck is only two colors, is it really a big deal?

HikingStick wrote:So, would it be better for the deck color to be based on the color of mana sources in the deck, rather than on the cards that are cast? In that case, however, we end up with the same scenario if someone is using a dual land for the wow factor, but has no intention of tapping for the second land color.

It can also be an issue with lands that tap for all 5 colors, what if you've got the obscure deck that uses all 5 color lands (City of Brass, Cavern of Souls, Reflecting Pool, Gemstone Mine, Lotus Vale, ECT) and you're only running 4 colors, I think that if a change is made that it should be just that you can manually list the color, format, and varient, some people don't like to list their commander as part of the decklist because it's not in the deck but that doesn't make it a 99 card vintage deck.

HikingStick wrote:In the overall scheme of things, how important is that designation? If you know the deck is only two colors, is it really a big deal?

IMO it's only an issue if you want other people to be able to look at your deck list when they're working on decks, for example I was looking at Dredge lists and I struggled to find lists that actually applied to mine because anything with a reanimation target was automatically extra colors and I couldn't tell which had the same base colors as mine.