K'rrik, Son of Yawgmoth

2019-08-23 If a cost contains a mana symbol that may be paid in multiple ways, such as {B/R}, {B/P}, or {2/B}, you choose how you'll pay it before you do so. If you choose to pay {B} this way, K'rrik's ability allows you to pay life rather than pay that mana.
2019-08-23 K'rrik's ability doesn't modify or reduce costs you pay. It changes only how you may pay those costs.
2019-08-23 K'rrik's ability lets you pay 2 life for {B} in any cost you pay, including casting costs, activation costs, and even costs for special actions (such as morph). Any time you pay mana, that's a cost.
2019-08-23 K'rrik's last ability resolves before the spell that caused it to trigger. It resolves even if that spell is countered.
2019-08-23 You can't pay 2 life to pay for generic mana in costs you pay, even if an effect says that you must spend black mana to pay that generic mana.

Card is in preconstructed decks:

mtg.wtf