Pack Leader
Creature — Dog
Other Dogs you control get +1/+1.
Whenever this creature attacks, prevent all combat damage that would be dealt this turn to Dogs you control.
He will be your loyal champion, and his pack your protectors. All he asks for is a full belly, a spot by the fire, and all the love in your heart.
Rudy Siswanto
The List (PLST)
• #M21-29Rulings
Because damage remains marked on a creature until the damage is removed as the turn ends, nonlethal damage dealt to a Dog you control may become lethal if Pack Leader leaves the battlefield during that turn.
(wotc • 2020-06-23)
Once Pack Leader attacks, its effect prevents damage that would be dealt to Dogs you control even if Pack Leader leaves the battlefield.
(wotc • 2020-06-23)
Rulings
Because damage remains marked on a creature until the damage is removed as the turn ends, nonlethal damage dealt to a Dog you control may become lethal if Pack Leader leaves the battlefield during that turn.
(wotc • 2020-06-23)
Once Pack Leader attacks, its effect prevents damage that would be dealt to Dogs you control even if Pack Leader leaves the battlefield.
(wotc • 2020-06-23)