603.1 Triggered abilities have a trigger condition and an effect. They are written as “[Trigger condition], [effect],” and begin with the word “when,” “whenever,” or “at.” They can also be expressed as “[When/Whenever/At] [trigger event], [effect].” A triggered ability is said to “trigger” whenever the above-mentioned [trigger condition] has been met.

Generally speaking, the point at which a player needs to demonstrate awareness of a triggered ability is after it has triggered, but no later than when that ability would “first matter.” For triggers with physical actions, a verbal acknowledgement of the trigger is not sufficient; the physical actions must be performed at the correct time. There are thousands of triggers in the game, and they each work a little differently. Some require targets, some require choices made by opponents, some have physical actions on resolution, some are invisible, etc., so when a trigger “first matters” is not something that can be defined in a single sentence. We’ll revisit this phrase throughout this section.

This is another way of saying that in order to figure out whether or not a player has missed a trigger, you must first consider what the ability does. The point at which the ability first matters depends on which of the below four categories that ability belongs to. Note that this is intended to be an exhaustive list — all triggered abilities in the game may be categorized in one of the following ways.

These are triggered abilities that first matter as they are put onto the stack. In order to avoid missing these triggers, the controller of these abilities must remember to make the choices involved with these right away.

Examples: Advocate of the Beast, Archaeomancer, Blightcaster

For the purposes of triggered abilities, the choice of a “target opponent” is automatically assumed in a two-player game. The controller is not required to explicitly make this choice to avoid missing the trigger. A player isn’t off the hook just yet, though — he or she will still need to demonstrate awareness at some later point according to whichever of the three remaining groups the effect fits into. Also, the opponent is not assumed to be the target when the trigger requires a “target player,” even if it’s “obvious” that you want to target the opponent.

These are triggered abilities that first matter at resolution. In order to avoid missing these triggers, the controller of these abilities must remember to make the choice or take the visible action when the trigger would resolve (or prompt the opponent to do so).

Examples: Ainok Guide, Burning Earth, Abzan Skycaptain

As it turns out, this is by far the most common type of triggered ability in the game. Most triggered abilities involve obvious visible actions such as drawing cards, moving objects from zone to zone, or modifying the state of permanents. Note that life totals are considered part of the visible representation of the game — this implies that triggered abilities that cause a player to take damage or gain life first matter at the point that a score pad should be updated.

When making this determination, a lot of benefit of the doubt is given to players — they usually have to go well out of their way to show that they’ve missed a trigger. For example, if a player casts a spell during upkeep, it is assumed that upkeep triggers are still on the stack, not missed.

These are triggered abilities that first matter at the point at which an opponent would first take what would otherwise be an illegal action. In order to avoid missing these triggers, the controller of these abilities must announce the trigger at the correct time and/or actively prevent an opponent from taking an action that wouldn’t be possible had the triggered ability resolved.

Examples: Brine Elemental, Lavinia of the Tenth, Wall of Frost, Pyreheart Wolf

Players are under no obligation to assume the resolution of a triggered ability controlled by an opponent that has not yet been acknowledged. Players are welcome to behave as if it an unacknowledged triggered ability belonging to an opponent was forgotten, but they must expect to be stopped by that opponent if they begin to take an action that the resolution of the triggered ability rendered illegal.

For example, suppose Abelard attacks Nutella with a Pyreheart Wolf and doesn’t immediately mention his trigger. Nutella is allowed to try to declare her animated Mutavault as a blocker. If Abelard does not speak up about this blocking assignment being illegal before taking a later action or continuing with combat, Abelard has missed his trigger.

If a player chooses to perform this “Missed Trigger gambit,” so to speak, he or she risks giving away information like the identity of cards in his or her hand or intended plays. Worse yet, a player banking on a forgotten trigger of this type may lock himself or herself into plays he or she would otherwise not want to take. In the above example, if Abelard prevents Nutella from blocking with her Mutavault, Nutella would not get to undo the activation of Mutavault’s ability and would not get a “refund” for the mana spent.

These are triggered abilities that aren’t immediately visually apparent, but would first matter at some point after resolution. Examples include causing a creature to gain some ability, giving a creature a power and toughness bonus (but not a counter), or dealing damage to a creature. Each of these is an example of an effect that isn’t usually represented visually.

However, the result of these effects may cause some later visible change to the game state. For example, suppose Norville controls an Aether Flash at the time that Anise casts a 3/3 Hill Giant, and neither player mentions the trigger. If, later that turn, Norville deals 1 additional damage to Anise’s creature, Norville will have not missed his Aether Flash trigger if he prompts Anise to put her creature into the graveyard at that time. In this case, Aether Flash’s trigger first matters at the point when Anise’s creature receives lethal damage.

Examples: Boros Elite, Steppe Lynx, Zhur-Taa Ancient, Emrakul, the Aeons Torn

This is something that people get hung up on, and will be addressed in more detail below. But the default assumption of the opponent should be that the trigger happened when it was supposed to.

As convenient as it may be for judges to consider previously acknowledged but problematically-executed triggered abilities to be missed, they must nonetheless be treated as a different infraction.

For example, suppose Acetone attacks Neutrino with an unblocked Arbor Elf equipped with Sword of Feast and Famine. During the combat damage step, Acetone untaps his lands but both players forget about Neutrino discarding. Even if this is noticed during the post combat main phase, this must be treated as a Game Rules Violation by either rewinding the game or applying the appropriate partial fix, and not by simply asking Neutrino if she’d like the discard ability to be placed on the stack. It is also a Game Rules Violation if you acknowledge a trigger at the proper time or earlier, and then, because of multiple things on the stack, you forget to resolve it.

The first sentence implies that it is impossible to miss, for example, Grave Betrayal’s triggered ability. However, the second sentence means that the delayed triggered ability itself, which makes a visible change to the game state, may be missed if not acknowledged by the time it would first matter. If Ned’s creature dies while Abe controls a Grave Betrayal, the trigger happens. However Abe can still miss the resulting delayed trigger by later passing the turn without returning the creature to the battlefield or otherwise calling attention to the ability. This is a concession to the way players play. The delayed triggers creation isn’t “relevant” but its resolution is.

For example, the Storm ability of Empty the Warrens is not considered missed even if the spell’s controller does not specifically announce the trigger before passing priority after casting the spell. However, if that player then forgets to put the additional Goblins onto the battlefield before moving on with his or her turn, the Storm trigger would be considered missed after all. Again, this is a concession to the way players actually play Magic.

Triggered abilities that don’t matter are few and far between. When determining whether or not a triggered ability would have no impact on the game, you should not take into account how likely an opponent is to perform some optional action permitted by the ability. For example, a tapped Desecration Demon should still have its triggered ability acknowledged and the opponent should be prompted for choice of a sacrifice even though Desecration Demon is already tapped.

Another example of a triggered ability that would have no impact on the game may occur in a scenario in which a player attacks with only a Chasm Drake. The Chasm Drake itself is the only legal target for the ability, but giving a Chasm Drake a second instance of Flying would be redundant. So, this trigger would not matter and intentionally ignoring it would not be an infraction.

This is another very important detail to keep in mind when observing a match as either a spectator or judge. Simply asking a player if he or she acknowledged a triggered ability is itself a reminder of that ability. Worse still, calling attention to a particular triggered ability before it would first matter provides an opportunity for a player to acknowledge it then. Depending on the circumstances, making this mistake could be perceived by an opponent as a lack of impartiality or even as significant coaching. Furthermore, if a spectator makes this mistake, it could be considered Tournament Error — Outside Assistance. Clearly, this should be avoided.

The only exception to this, of course, is when a judge needs to issue a Warning or investigate a player for Cheating. The needs of the tournament — specifically, ensuring its integrity — exceed those of an individual match.

(Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.) In this scenario, this ability first matters during the combat damage step. This is a triggered ability that affects the game state in non-visible ways. By indicating the Knight is attacking for 2 damage, the player has missed her trigger, even if she is stating the knight is attacking for 2 prior to the combat damage step.

(At the beginning of your upkeep, if this card is suspended, remove a time counter from it) In this scenario, this ability first matters before the player draws for the turn. This is a triggered ability that causes a change in the visible game state. Once the player draws a card, he has advanced the game past the point where the visible game state would first be altered had the trigger resolved.

(When Azorius Arrester enters the battlefield, detain target creature an opponent controls.) In this scenario, this ability first matters before the player passes priority. This is a triggered ability that requires its controller to choose targets.

In this scenario, this ability first matters before the player indicates that she has moved past the combat phase. This is a delayed triggered ability that causes a change in the visible game state.

It’s pretty easy to forget triggers, there are a lot of them and there is often no visual component to them. They are also typically beneficial, and the ones that aren’t, the opponent is motivated to be aware of. Furthermore, triggered abilities have sort of a “natural” handling if they’re forgotten — most of the time, they can simply just not happen without any additional cleanup or situation-specific remedy being needed.

So, while forgetting your trigger is not to be harshly penalized, intentionally missing your trigger is much more serious. Note the subtle usage of the word “may,” in the sentence above. If you suspect a player of cheating, read the definition of Cheating to see if it applies. Another exception to this being Unsporting Conduct – Cheating is if the player in question were not aware that intentionally ignoring one’s own triggered abilities is against the rules.

Remembering one’s trigger is always the responsibility of the player who controls the ability. This is usually, but not always, the controller of the object that has the ability. It doesn’t matter that the triggered ability may allow an opponent to take an optional action — the controller of the trigger is responsible for remembering it and prompting the opponent to make a choice. Examples include things like Frost Titan, Desecration Demon and Rhystic Study.

One of the many skills tested in Magic is the ability of players to remember their own triggered abilities. Players should not be punished for the inabilities or poor memories of their opponents.

Why might a player want to remind an opponent of his or her triggered ability? It’s possible that the triggered ability might be subjectively bad for that opponent. For example, suppose Absinthe is at 1 life and controls a Dark Confidant whose triggered ability has been missed several times earlier in the game. Given the player’s now low life total, Novocain would have a high incentive to make sure that the trigger happens when it’s supposed to.

Triggered abilities are assumed to be remembered not only by both the player and opponent, but also by any judges watching the match. By failing to acknowledge a triggered ability by when it would first matter, the player effectively disproves this assumption. This sentence also answers the question of “How can I tell if my opponent missed his exalted trigger?” You are to assume it happened until you have evidence that it didn’t. This is an important point. Just as you can acknowledge a trigger happened earlier than required, you can also indicate the trigger didn’t happen earlier than required. For example, if you untap with a Kragma Butcher and say nothing indicating the trigger, it is assumed to be a 4/3. However, the controller can indicate earlier than combat damage that he forgot the trigger. Attacking with an Ensnaring Bridge on the battlefield might indicate its trigger was missed. Answering “what’s that creature’s power?” with “it’s a 2/3” is an indication it was missed.

To repeat an earlier annotation, players are never responsible for remembering their opponent’s triggers. Players are allowed to remain quiet about triggers controlled by an opponent being missed, even if the triggered ability would do something harmful to its controller. There is never a time when a player should be issued an infraction, be it Unsporting Conduct — Cheating, Game Play Error — Failure to Maintain Game State, etc., for either accidentally or intentionally not calling attention to an opponent’s Missed Trigger. Players do not have to help their opponents beat them; however, they cannot trick their opponents into missing triggers.

Suppose Amaranth controls Cathedral of War and attacks with her single 2/2 Bear Cub, proceeding through to the declare blockers step without mentioning the triggered ability. After declaring blockers, Niles considers casting Shock targeting the unblocked Bear Cub.

Niles has two options — he could simply cast Shock, targeting the Bear Cub, hoping that Amaranth forgot about the trigger. However, by doing so, Niles risks Amaranth acknowledging the trigger by afterward not putting the Bear Cub into the graveyard. In other words, just because Amaranth didn’t explicitly announce her trigger doesn’t mean she’s yet missed it — the point at which the trigger would first matter in this case would be after Shock resolves. So, if Niles were to attempt this ploy, he risks wasting his Shock.

Alternatively, Niles could first ask Amaranth if any abilities have modified Bear Cub’s toughness. This is free information, so Amaranth would be required to answer it honestly and completely. With this option, the point at which Cathedral of War’s trigger would first matter would be when Amaranth answers the question.

This may seem somewhat unsatisfactory to Niles, since asking questions about the toughness of the Bear Cub might remind Amaranth about her trigger and give her one last opportunity to acknowledge it. However, as the IPG says, “triggered abilities are assumed to be remembered until otherwise indicated.” Niles should be reminded of this by judges as needed.

It isn’t up to the opponent to confirm whether or not a player has missed their trigger before making a play that may be illegal. For example, if Anna is attacking with Pyreheart Wolf, it is not illegal for Nolan to block the wolf with one creature. When that block is proposed, it is up to Anna to indicate the illegality of the block or not, and this will determine if the play needs to be rewound.

This sentence has a lot of philosophical weight, and provides guidance on how to deal with triggered abilities controlled by one player that trigger during another player’s turn. Triggered abilities fitting this description deserve some special consideration. Generally speaking, the active player — that’s the player whose turn it is — controls the flow of the game by taking each turn-based action as he or she moves through that turn’s steps and phases. Magic players rarely explicitly pass priority, most of the time just shortcutting through nearly all of the technical rigmarole.

The reason that policy allows for players to acknowledge triggers just after an opponent takes a game action that would otherwise cause the trigger to be missed is precisely because players do not usually prompt their opponents for actions before moving ahead with their turns. For example, players will often proceed straight from their main phase to declaring attackers without asking the opponent if he or she wants to first do anything — such as announcing any beginning of combat triggers.

The Missed Trigger policy was written to address the way that players already play the game and not the other way around.

A player that says nothing about his or her opponent’s Braids, Cabal Minion trigger before attempting to draw for the turn hasn’t committed an infraction. If an opponent speaks up about the trigger as soon as the card is drawn, the trigger has not been missed.

This sentence simply further clarifies what has been stated above. If a player has a trigger that would happen on an opponent’s turn, that player has to actively “miss” it, they can’t be moved past the point of acknowledging the trigger by the active player’s actions in their own turn. It is also to prevent players from trying to use a loophole in the policy to rush past their opponents trigger, so that they can deny their opponent the trigger. This sentence closes the perception of that loophole. You cannot force your opponent to miss his or her trigger.

From MTR 4.3:

Due to the complexity of accurately representing a game of Magic, it is acceptable for players to engage in a block of actions that, while technically in an incorrect order, arrive at a legal and clearly understood game state once they are complete.

All actions taken must be legal if they were executed in the correct order, and any opponent can ask the player to do the actions in the correct sequence so that he or she can respond at the appropriate time (at which point players will not be held to any still-pending actions).

An out-of-order sequence must not result in a player prematurely gaining information which could reasonably affect decisions made later in that sequence.

This means that, in certain situations, players may acknowledge a trigger as part of a block of actions, some of which may technically be later than the point at which the trigger would first matter, without the trigger being missed.

For example, a player may, in quick succession, sacrifice Pitchburn Devils to pay the cost of his Carrion Feeder’s activated ability, then put a counter on the Carrion Feeder, and then say “you take 3,” without Pitchburn Devils’s trigger being considered missed. If the player takes these actions all at once without leaving an opportunity for the opponent to indicate responses or provide additional information, this should usually be ruled a legal out-of-order sequence of actions.

A player could not, however, remove the last counter from a Rift Bolt, then draw for the turn, and then say “I’ll Rift Bolt your creature.” Even if the player performs these actions in quick succession and without the opponent saying anything, he or she would still have gained the knowledge of the card drawn for the turn before choosing his Rift Bolt target. This should usually be ruled a Missed Trigger.

“Oh, you drew before paying your Echo cost? That’s cool, just sacrifice your guy now” is the way that casual players have handled this kind of error for years — this piece of policy has significant precedent. Indeed, much of policy is built around the pre-existing habits and expectations of players. The above sentence is one of the most clear-cut examples of this in the entire IPG.

Examples: Masticore, Pact of Negation, Transguild Promenade. We will see the next two sentences detail how to “resolve it”.

This type of triggered ability, known as delayed zone-change triggers, frequently exist in order to “clean things up.” While this type of trigger includes a lot of delayed sacrifices of tokens (Kiki-Jiki, Mirror Breaker, Thatcher Revolt, Geist of Saint Traft, etc.), it also includes many abilities that are utterly vital to the continued use of the associated object. For example, the delayed triggered abilities that return Ætherling and Obzedat, Ghost Council to the battlefield are included in this category. These triggers are necessary for the creatures’ controllers to be able to continue using them that game. This will be an important concept shortly. We will see in the next description details on how to “resolve it”.

So the opponent’s choice is for the trigger to occur “now” or “in a moment.” “Never” is not an option for these types of triggers.

Note that policy allows for the object to be returned when a player would get priority at the start of the next phase, and not step. The timing option here allows for a bit of control over creatures appearing and disappearing from the battlefield mid-combat. Putting the control in the hands of the opponent is acceptable because the opponent isn’t the one who missed his or her trigger, and this allows the opponent to minimize the impact of the player “suddenly” remembering the trigger.

Resolving a delayed zone-change trigger that returns a creature to the battlefield at the start of the next phase means that if a player notices his or her own Missed Trigger during his or her opponent’s end step, the opponent may choose to have the creature remain exiled until the player’s upkeep. That means this creature will have summoning sickness and won’t be able to attack that turn. Of course, an opponent can still opt to have that creature returned to the battlefield when a player got priority during that end of turn step if he or she really wanted to.

Finally, wherever the opponent chooses to place the trigger, it is resolved immediately, without using the stack. This is to prevent responding to these triggers that should have already happened. You wouldn’t want a pact trigger placed on the stack, then the player casts a card draw spell in response to dig out a Stifle, would you?

Notably, the opponent gets to choose the “when,” but not the “if.” One reason for this has to do with the fact that many zone-change triggers are, as pointed out above, utterly vital to the continued use of the associated objects. If an opponent got to choose whether these triggers happened at all, this infraction might be a little too harsh on players who, for example, suddenly find their Ætherling exiled forever just because they forgot to return it last turn. From the previous section: “Triggered abilities are common and invisible, so players should not be harshly penalized when forgetting about one.” So, policy has to have some special consideration here.

Also of interest is that even though these abilities don’t expire, players are still under no obligation to remind the opponent of their existence. A player is perfectly within policy by remaining quiet for several turns despite having noticed that his opponent’s Obzedat, Ghost Council never returned from exile. And don’t forget the triggers on Pact of Negation and his buddies. The default action will be resolved even if it’s remembered two turns later.

If it’s been more than a turn since the trigger was missed, the ability is skipped with no further resolution. Remember, though, that if that ability were detrimental for the controlling player, he or she should still receive a penalty no matter how long it’s been.

For example, if the missed triggered ability lasts “until [some amount of time]” or “for as long as [some condition],” then the ability has a duration. If a Missed Trigger is not noticed until after the amount of time has elapsed or the condition is no longer true, the ability is skipped with no further resolution.

Examples: Battlegrace Angel, Colossal Whale, Nivix Cyclops

If the triggered ability isn’t covered by the previous two paragraphs, the opponent chooses whether the triggered ability is added to the stack.

So, run through the checks above. If none of them fit, this is our default.

The opponent should be explicitly asked if he or she would like the ability to go on the stack. Judges should not just assume that players won’t want triggers harmful to them or helpful to an opponent to be skipped, no matter how silly asking might seem.

One case in which it might not be possible to insert the trigger in the appropriate place on the stack is if some of the other abilities that triggered at the same time as the Missed Trigger have since resolved and are no longer there.

When placing Missed Triggers on the stack, players may make choices only about objects that could have been chosen had the trigger not been missed. Because there is one-turn expiration on placing Missed Triggers on the stack, it’s unlikely that many permanents have moved around in the interim. For this reason, remembering which objects were in which zones shouldn’t be too taxing to either player’s memory.

If a player unintentionally misses his or her own Smokestack trigger (At the beginning of each player’s upkeep, that player sacrifices a permanent for each soot counter on Smokestack), but this is not noticed until after the player has moved into his first main phase and played a land, the player should receive a Warning and the opponent should be asked if he or she would like the trigger to go on the stack. If the trigger is placed on the stack, then the player may not choose the land he or she just played for the turn as one of the permanents to sacrifice.

“Usually detrimental” triggers are often all-downside triggers that have been added to some card in order to balance out some other above-the-curve stats or other beneficial effects. Other times, “usually detrimental” triggers are ones that “clean up” a game state by causing the controller to sacrifice some temporarily-created tokens or to give a momentarily nullified permanent back to an opponent.

Furthermore, “usually detrimental” means that you should consider the card associated with the trigger in a vacuum and not take into account any game-specific information in order to determine whether or not a trigger is detrimental. Toby Elliott once said (on his blog) that one guideline for making this determination is to ask yourself: “If the trigger didn’t exist, would the card be played?” If the answer is no, then the ability is probably not detrimental.

In theory, all triggered abilities in Magic could be classified as either detrimental or non-detrimental — in fact, a small group of judges are endeavoring to accomplish this very thing with the Missed Trigger Guides project.

When determining if a trigger is ‘usually detrimental,’ we do not look at the game state. A Dark Confidant trigger at 20 life is the same as a Dark Confidant trigger at 1 life. This is because we want consistent rulings and there is no way to take game state into account and have every judge answer the same way.

However, we are allowed to consider symmetrical abilities differently based on who is affected. What exactly is a symmetrical ability? Symmetrical abilities are triggered abilities that meet two conditions. They: 1. are likely to trigger multiple times per game, triggering for different players 2. have the same effect on both players.

Examples include Howling Mine, Sulfuric Vortex, and Burning Earth. A symmetrical ability may either do something positive to both players, or do something negative to both players, but would never do something positive to one player and negative to the other player. Furthermore, a symmetrical ability must have its effect on each player during separate instances of the same ability. For example, Sire of Insanity’s triggered ability (At the beginning of each end step, each player discards his or her hand.) is not symmetrical.

If a player misses a symmetrical trigger that would be either bad for him or her or good for an opponent, he or she should receive a Warning.