Damage and Kill Attribution

The player performing a game action is responsible for it unless the rules assign responsibility differently. A condition such as “when you deal damage” checks that responsibility. A procedure of the game can perform an action without any responsible player unless a specific rule assigns one.

Consider the Core Rules’ shared-kill example: your spell tells each player to kill one of their own units. You perform your kill and the opponent performs theirs. Your opponent’s action does not become yours just because your spell instructed it. For a later condition requiring you to kill, ask who actually performed that particular kill before asking which spell it came from.

If an effect simply instructs damage, that effect is normally the source: the effect credited with dealing that damage. An ability dealing damage can count both as the ability and as the object that created it. If the text instead specifically tells a unit to deal damage, that unit is the source rather than the instructing spell or ability. Its controller, the player who controls that unit, is normally responsible for its damage.

Challenge is the Core Rules’ comparison: the chosen friendly and enemy units deal their Might as damage to each other. Although you played the spell, each unit’s controller is responsible for that unit’s damage. Your opponent’s “when you deal damage” abilities can therefore see the damage their unit deals. Do not call both directions your spell damage. In Combat, the participating units on the opposing side are the sources of the damage assigned to a side.

Damage remains marked on each unit and can be attributed to the responsible player for checks referring to that player’s damage. A kill caused by lethal damage is checked later. For a spell or ability dealing lethal damage, the kill in the immediately following Cleanup is attributed to the spell or ability that dealt that damage, and the responsible damage player is responsible for the kill. Combat Cleanup assigns kill attribution to the Combat damage sources and their controller.

An abstract example separates earlier damage from the finishing event: a 5-Might unit already has 2 damage; a spell now deals 3. It has 5 marked damage and dies at the following check. That spell and the responsible damage player receive the relevant immediate-Cleanup attribution. Do not automatically credit every earlier damaging card with the kill merely because some of its damage remained marked.

A kill instruction receives attribution to its spell or ability. An ability’s kill can also be attributed to the object that created it. For wording requiring an action “with” an object, check attribution, control of the relevant spell or ability, and responsibility for the action. These are requirements together, not interchangeable alternatives.

An Equipment’s Effect Text, the separate text it adds to the unit it is attached to, can grant an ability to that unit. Such a granted ability counts for both objects for these action-with-object checks. Keep the unit and Equipment controllers distinct: sharing attribution does not transfer their control or give both players responsibility for the same action. The player controlling the actual ability and responsible for the action is the relevant player for a “you” check.

The official FAQ confirms Imperial Decree’s delayed-trigger interaction with Immortal Phoenix. The delayed ability, created by the spell to act at a later event, receives kill attribution, and the spell that generated it also receives that attribution. If the same player controls that ability, is responsible for the kill, and owns Phoenix in the Trash, the required spell-kill condition can be fulfilled.

Follow the timeline: the spell generates its delayed trigger → later qualifying damage causes that trigger → the trigger resolves its Kill instruction → check the responsible player and the spell-linked source → Phoenix’s Trash trigger can be created. Do not credit the earlier damage spell with this explicit delayed Kill merely because it caused the damage event. Read the effect performing the actual kill.