Commander Color Identity

[Gorzo]

I have 2 questions about color legality in commander.

1) what exactly determines a cards color identity for the sake of a card being legal in a commander deck? I've heard some claim CMC color alone determines it, and also some say that activated ability costs are also determining factors. For example, say your general is {Ulasht, the Hate Seed}. His identity is {R}{G}. No doubts there. But can {Jund Battlemage} be in its deck? Sure, you cant produce black for mana for its one ability, but i'd be using it as a cheap token pooper Anyway for {G}. It's mana cost is simply red. Does that activated ability prevent Battlemage from being in the deck? What's the official ruling here?

2) how does a flip card with a different color on the back side that doesn't match work with color restrictions? {Garruk Relentless} in the same deck, for example?

[Deathstorm]

What about a card like {debtors knell} can it be used in a mono color commander deck

[BlackJester]

Commander Color identity is all mana symbols on the card:
903.4. The Commander variant uses color identity to determine what cards can be in a deck with a certain commander. The color identity of a card is the color or colors of any mana symbols in that card's mana cost or rules text, plus any colors defined by its characteristic-defining abilities (see rule 604.3) or color indicator (see rule 204).

The back of double faced cards counts towards their color identity.
You can't include cards with colors outside the commander's identity colors.
903.5c A card can be included in a Commander deck only if every color in its color identity is also found in the color identity of the deck's commander.

tl;dr No battlemage, no off-color hybrid

/hatin' 😜

[Gorzo]

Dang, I was really hoping {Garruk Relentless} could fit into my token deck. But at least least I have an official answer. Thanks Jester, great hater of plans

[BlackJester]

Yeah, the rule has been handed down from the days of yore, long before hybrid mana. I'd rather they change the ruling. 😏

[Deathstorm]

Same here that's a terrible rule

[Desolatus]

Would that mean that any artifact card with mana symbols in it's text box would be those colors? Or is it colorless?

[BlackJester]

Would that mean that any artifact card with mana symbols in it's text box would be those colors? Or is it colorless?

Color =/= Color identity.

{Horizon Spellbomb} is colorless, but it's color identity is {G}.

[Desolatus]

Ah, okay. Thanks BJ. So playing Artifact spells doesnt effect {Quirion Dryad}.

[Hays413]

Ah, okay. Thanks BJ. So playing Artifact spells doesnt effect {Quirion Dryad}.

Correct

[scarsabrex]

unless it is a colored artfact.

[Hays413]

unless it is a colored artfact.

Also correct