Children of Korlis

• WWizards of the Coast2021-03-19
  Official Ruling
  The life you gain is based on the total amount of life you lost, not the difference in your life total from when the turn started. For example, if you lose 5 life and gain 3 life before activating the ability, the ability will cause you to gain 5 life, not 2.
• WWizards of the Coast2021-03-19
  Official Ruling
  If your life total becomes 0 or less, you'll lose the game before you can activate the ability of Children of Korlis.

Rulings via Scryfall