Cast Mourning by paying 2 life if able, or otherwise.
Each creature you control's extort ability triggers.
Resolve the first extort trigger, causing you to pay 2 life if able, or W/B otherwise, causing each opponent to lose 1 life and you to gain that much life.
Repeat step 3 for each remaining extort trigger.
Resolve Mourning, attaching it to a creature you control.
Activate Mourning by paying 2 life, returning it from the battlefield to your hand.
Repeat until an opponent loses the game due to having 0 or less life.
This fascinating loop turns a humble Aura into a relentless engine of drain and gain by leveraging the life-paying alternative cost of K'rrik, Son of Yawgmoth. Because Mana Matrix reduces the cost of enchantment spells, and K'rrik lets you substitute life for black mana, you can cast and bounce Mourning repeatedly for pure life instead of spending actual mana. Every single iteration of casting Mourning triggers the extort ability granted to your board by Pontiff of Blight, weaponizing your life payments to bleed out your opponents while effortlessly padding your own health total.