Trigger Conditions and Source Changes

A condition placed immediately after the trigger condition is part of that trigger condition. It must be satisfied when the event is evaluated. A conditional statement inside the effect is instead checked when that instruction executes. Do not repeatedly retest a source-location trigger condition at resolution unless a later instruction actually needs that location.

The Core Rules compare two cases. Sona’s end-of-turn ability requires her to be at a battlefield when that end-of-turn trigger condition is fulfilled. Once the ability exists, moving or removing her in reaction does not by itself stop its rune-readying instructions. Loose Cannon’s beginning-phase draw places its low-hand-size condition inside the effect instead. That hand-size check happens when the draw instruction executes, so intervening draws or discards can change its result.

For a trigger on the first, second or another numbered occurrence, track the specified occurrence. If several qualifying instances happen simultaneously when that condition is met, the ability’s controller, the player who controls it, chooses one of those events as the event that triggers it and the ability triggers only once. Do not treat a simultaneous group as several independent chances to satisfy the same numbered trigger.

For example, an ability watches the first death of another friendly unit each turn. Two other friendly units die together, and this is the first qualifying death event for the turn. Choose one death as the event that triggers the ability; create one draw ability, not two. A different wording such as “Whenever another friendly unit dies” does not carry that same first-time limitation. Read the complete condition, including any once-per-turn restriction.

Triggered abilities on permanents normally work on the board. A permanent is a unit or gear that remains there after being played; runes, legends and battlefields are different categories. An ability that works outside the board states where it works. Evaluate ordinary triggers after the event has been processed. Entering the game area where the ability works at the same time as the condition is met can allow a trigger. Leaving that zone at the same time normally prevents the source from observing the event.

The Core Rules’ contrast is useful. Immortal Phoenix has a trigger active in the Trash for your spell kill; it can trigger if that very spell kill put Phoenix there. A board observer like Viktor does not trigger for another unit dying in the same action that removes Viktor from the board. Own-death abilities such as Deathknell have their separate pre-departure capture procedure; do not generalize that exception to every observer.

An effect can grant or remove a unit’s abilities. A granted trigger must be active when its condition is evaluated; gaining it after an earlier event does not retroactively trigger it. Dependent keywords can make text active at the same moment as its trigger event, in which case the rules evaluate that active trigger.

A unit gains “When I attack, draw 1” before it is designated attacking. Its first qualifying attack event creates the draw ability. If a response later removes that granted text, the already-created ability does not disappear merely because the unit no longer has the text. If the grant instead happens after that attack event, it does not create a draw for the past attack. Having permission to use an ability now and having an ability already on the Chain are separate facts.

An ability normally begins under the controller of its source, or the source’s owner when the source is in a non-board zone. A later control change of the source does not transfer that created ability. If an effect changes control of the ability itself, that is a different change; terms such as friendly and enemy are assessed relative to its controller when the instruction executes.

For a full timeline: you control a unit with an active granted attack trigger → its attack event creates your ability → an opponent gains the unit → the ability remains yours → resolve its own legal instructions. If the instruction also uses current source information, check that separately. Retaining control of the ability does not freeze the source’s Might or location.