The rules for commander, from the Comp rules:
207.2. The text box may also contain italicized text that has no game function.
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).
903.4b Reminder text is ignored when determining a card's color identity. See rule 207.2.
Extort is fair game; It is a keyword ability, and the troubling hybrid mana only appears in the reminder text.
Though, for the deck: you have 2 copies of
Shrieking Affliction.