Does phyrexian mana in a card's mana cost count toward its color identity in Commander?

In Commander, a card's color identity is determined by every colored mana symbol that appears anywhere on the card — in its mana cost, rules text, or elsewhere. This is governed by CR 903.4, which states that a card's color identity is its color plus the color of any mana symbol in its rules text.

Phyrexian mana symbols (written as {W/P}, {U/P}, {B/P}, {R/P}, or {G/P}) are hybrid mana symbols with a color component. CR 202.2e explicitly identifies Phyrexian mana symbols as having a color, so they contribute that color to the card's color identity regardless of whether a player actually pays life instead of mana when casting the spell.

This means a card like Birthing Pod ({3}{G/P}) has a green color identity, and Gut Shot ({R/P}) has a red color identity. You cannot include Gut Shot in a mono-blue Commander deck, even though you could theoretically pay its cost entirely with 2 life.

A concrete example: Imagine you're building a mono-white Commander deck. You cannot include Phyrexian Metamorph ({3}{U/P}) because the {U/P} symbol gives it a blue color identity (CR 202.2e, 903.4), which falls outside white's identity.

The key takeaway is that color identity is about the symbols printed on the card, not how the cost is actually paid at the table. Phyrexian mana's optional life-payment mode does not remove its color from identity calculations.