K'rrik, Son of Yawgmoth

A Phyrexian mana symbol contributes 1 toward the mana value of a card, even if life is paid for it. Specifically, K'rrik's mana value is always 7.

K'rrik's ability lets you pay 2 life for {B} in any cost you pay, including the mana costs of spells, activation costs, and even costs for special actions (such as morph). Any time you pay mana, that's a cost.

K'rrik's ability doesn't modify or reduce costs you pay. It changes only how you may pay those costs.