FINAL JUDGEMENT: Triggered Abilities

Today I want to talk about a rules area that generates loads of questions: Triggered abilities. Actually, I WANT to talk about Ferrett Counterspelling my Living Death for no good reason (he was going to die anyway) in that last multiplayer game, but I would start using language not suitable for a family audience, so I’ll stick to the rules 🙂

A triggered ability begins with "when", "whenever," or "at". The phrase starting with this word is the trigger condition. The templating goes ""When/whenever/at <condition>, do <effect>". As soon as the condition becomes true, the ability triggers, even in the middle of the resolution of a spell or ability. It will wait until a player receives priority to go on the stack.

For example, you control a Veiled Crocodile. "When a player has no cards in hand, if Veiled Crocodile is an enchantment, Veiled Crocodile becomes a 4/4 Crocodile creature." You then play Tolarian Wind, which reads "Discard your hand, then draw that many cards." You discard your hand. This triggers the Crocodile, but you still need to finish resolving the Tolarian Wind. You draw as many cards as you discarded. Then the Crocodile ability goes on the stack.

You see in the above example that there can also be a test in a triggered ability: "When/whenever/at <condition>, if <test>, do <effect>". In this case, the test is if the Veiled Crocodile is an enchantment. If the test were false, like if the Crocodile was already a creature, the ability wouldn’t trigger. Additionally, the condition is rechecked on resolution. If the Crocodile was an enchantment when the condition was met, the ability would trigger. If, somehow, the Crocodile was no longer an enchantment on resolution, the ability would simply fail to do anything.

Sometimes triggers give you the option of doing things. When <condition> you may <do something>. The choice of whether or not to do the action is made on resolution of the triggered ability. Foster reads: "Whenever a creature you control is put into a graveyard, you may pay 1. If you do, reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest into your graveyard." A creature is put into your graveyard, and the Foster triggers. When the Foster resolves, you choose whether or not to pay 1. If you do, then the effect takes place.

Now let’s get a little more complicated. We’ll get into multiple triggers. When multiple things trigger off the same effect, they’re put on the stack in APNAP (Active Player/Not Active Player) order. If one player controls multiple triggers, they’re put on the stack in the order he chooses.

Let’s use Foster again with Mortuary ("Whenever a creature is put into your graveyard from play, put that creature on top of your library.") You have a Gray Ogre in play. It goes to the graveyard, so both the Foster and the Mortuary trigger. You may put them on the stack in the order you choose. Remember that the stack resolves Last In, First Out (LIFO).

Scenario A: You put the Foster on the stack first, then the Mortuary. The Mortuary resolves, so you put the Ogre on top of your library. The Foster resolves, and you choose to pay 1. You reveal cards from the top of your library until you get to a creature. Obviously, the top card is the Ogre, so you put it into play.

Scenario B: You stack the Mortuary, then the Foster. Foster resolves and you choose to pay 1. You reveal cards from the top of your library until you reach a creature. Then Mortuary resolves, and you put the Ogre on top of your library.

Let’s get even more complex. Instead of a Gray Ogre, you have a Radiant’s Dragoons in play ("Echo. 2/5. When Radiant’s Dragoons comes into play, gain 5 life"); the Dragoons just came into play last turn. You know that the top card of your library is Gaea’s Blessing ("When Gaea’s Blessing is put into your graveyard from your library, shuffle your graveyard into your library.") At the beginning of your upkeep, the echo goes on the stack. When it resolves, you choose not to pay the echo goes, putting the Dragoons in the graveyard. Now:

Scenario A: You put the Foster on the stack first, then the Mortuary. The Mortuary resolves, so you put the Dragoons on top of your library. The Foster resolves, and you choose to pay 1. You reveal cards from the top of your library until you get to a creature. The top card is now the Dragoons, so you put it into play. The Dragoons’ ability goes on the stack. When it resolves, you gain 5 life.

Scenario B: You stack the Mortuary, then the Foster. Foster resolves and you choose to pay 1. You reveal cards from the top of your library until you reach a creature. The top card is the Blessing, so it triggers; the ability doesn’t go on the stack until a player gets priority. The second card is a creature, so you put that creature into play. The Blessing’s ability goes on the top of the stack. It resolves, shuffling your graveyard into your library. Then Mortuary resolves, but the Dragoons are no longer there, so the ability effectively does nothing.

Clear enough?

Abilities that trigger during a Phase or Step automatically go on the stack at the beginning of that Phase or Step. The same rules apply for multiple triggers or triggers from multiple players. Older cards that were worded "During <Phase>, do <something>" are almost all universally reworded to say "At the beginning of <Phase>…" Newer cards are correctly templated this way.

I’ve noticed some confusion over two particular combat triggers. There are two different templates. The first is "Whenever <name> blocks" or "Whenever <name> becomes blocked". This triggers once and only once, because a creature only blocks or becomes blocked one time per combat (because all blocks are declared together and are considered to be simultaneous). The second is "Whenever <name> blocks a creature" or "Whenever a creature blocks <name>". This will trigger for each creature blocked, or blocking, as the case may be. It’s basically the templating for the new, improved Rampage.

"Leaves Play" triggers are handled with special care. Since the permanent is no longer in play, if the ability wants to check anything about the permanent or the game state, it does so by looking back to just before the permanent left play. Continuous effects would apply. Let’s assume you have a White Knight (2/2), a Crusade (all white creatures get +1/+1) and a Diamond Valley (Tap, Sacrifice a creature: You gain life equal to the sacrificed creature’s toughness). If you use the Diamond Valley to sacrifice the White Knight, you gain 3 life.

"Comes Into Play" triggers see the permanent after any continuous effects apply. Imagine continuous effects as a cloud surrounding the world. Anything that wants to come into the world must first pass through the cloud. By the time it arrives, the cloud has affected it. For example, you have Angelic Chorus ("Whenever a creature comes into play under your control, you gain life equal to its toughness") and Humility ("All creatures are 1/1 with no abilities") in play. You summon the aforementioned Radiant Dragoons. It comes into play as a 1/1 creature (with no abilities), so you gain 1 life.

Once you see how they work in general, triggered abilities are moderately easy to figure out. They use the stack. They can be responded to, but once they’re on the stack, removing the source doesn’t remove the ability. They’re basically just like activated abilities, save that they simply wait for a condition (and things that stop activated abilities don’t stop triggered abilities).

If you’d like to know more about triggered abilities, check out the D’Angelo Rulings (http://www.crystalkeep.com/magic/index.html), section A.4 and the Comprehensive Rulebook, section 404.