Cards And Zones
Whose Damage or Kill Counts for an Ability?
Check both who performed the action and what dealt the damage or caused the kill.
RiftPal explanation · Answer first
The short answer
For "when you" do something, check which player is responsible for that action. For "with a spell" or similar wording, also check what the action is credited to. Playing the card that started the sequence does not automatically make every action yours.
RiftPal explanation
How it works
Damage normally comes from the spell or ability instructing it. If it tells a unit to deal the damage, that unit is the source instead. Its ControllerThe player who currently controls a game object and makes the choices assigned to that controller. Control is established differently for battlefields and other objects, and need not match ownership.View in Glossary is normally responsible for that damage, even if an opponent played the spell that instructed it. Combat damage comes from the participating units.
An explicit Kill instruction is credited to its spell or ability. When damage from a spell or ability causes a unit to die in the immediately following CleanupAn automatic rules check that handles winning, lethal damage and board conditions before play continues. It is not an action you choose or normally announce, and an ordinary check does not heal units.View in Glossary , that spell or ability gets credit for the kill, and the player responsible for the damage is responsible for the kill. Combat kills are credited to the combat-damage sources and their controller.
An ability's kill can also count for the card that created the ability. That includes a Delayed AbilityAn ability created by an effect to apply at a specified later time or during a specified window. It can persist after its source leaves the board.View in Glossary created by a spell; it can satisfy "you kill a unit with a spell" if you control that trigger and are responsible for the kill.
In practice
Example
Card example
Cull the Weak
Your spell tells each player to kill one of their own units. Each player is responsible for their own kill. Your opponent's kill does not become yours just because you played the spell.
Spell
Cull the Weak
Each player kills one of their units.