Historical Rules · 25 September 2020
Rule 614.9
Official source text from the 25 September 2020 Rules release
Some effects replace damage dealt to one creature, planeswalker, or player with the same damage dealt to another creature, planeswalker, or player; such effects are called redirection effects. If either creature or planeswalker is no longer on the battlefield when the damage would be redirected, or is no longer a creature or planeswalker when the damage would be redirected, the effect does nothing. If damage would be redirected to or from a player who has left the game, the effect does nothing.