In Commander, can you include a card in your deck if its only off-color mana symbol appears in reminder text?

In Commander, a card's color identity is determined by its mana cost and any mana symbols that appear in its rules text. However, mana symbols that appear exclusively in reminder text are explicitly excluded from this calculation. This is covered by CR rule 903.4, which defines color identity, combined with CR rule 207.2c, which clarifies that mana symbols in reminder text do not contribute to color identity.

Reminder text is the italicized text in parentheses that explains or reminds players of a keyword's meaning. Because it is templated flavor rather than functional rules text, the game treats it as invisible for color identity purposes. This means a card like Extort (which has a white/black Phyrexian-style hybrid symbol in its reminder text) does not gain white or black color identity purely from that symbol — though in practice Extort itself already has that identity from its card type and cost context.

A cleaner example: imagine a colorless artifact with a keyword whose reminder text reads '(You may pay {W} instead of its other cost).' Because {W} appears only in reminder text, this card has no white color identity and can be included in any Commander deck regardless of the commander's colors.

By contrast, if the same mana symbol appeared in the card's actual rules text (outside of parenthetical reminder text), it would contribute to color identity and could restrict which decks may include the card.

So the answer is a clear Yes — as long as the off-color mana symbol is confined entirely to reminder text, it is ignored for Commander color identity, and the card is legal in decks whose commander does not share that color.