“When” and “If” are two of the trickiest words in the Yu-Gi-Oh! TCG. Both of them are used on a wide variety of effects, and both are involved in the rules regarding what is commonly referred to as “missing the timing”.
Though not as common as the first, “If” is surprisingly easy to understand. For this word, timing is never an issue. All that matters is “If” something happened. Doesn’t matter when it happened, just that it happened. Simple. (There is one exception, and that’s Eclipse Wyvern; however, that is for entirely different reasons, and it deserves its own article.)
“When”, though, is not as easy to grasp. And to make matters worse, Trigger effects aren’t the only effects that are subject to this word’s complexity. ANY optional effect that uses the word “when” in its timing clause- that is, the section of the effect that tells you when you can activate it, i.e. “When this card is sent to the Graveyard:”- can have a lot of crazy timing issues come up.
We’re all familiar with the “missing the timing” rules regarding optional “When” effects. For those of you who aren’t, here’s a quick refresher: Suppose you have a Daybreaker in your Graveyard, and another in your hand. Your opponent activates Mystical Space Typhoon to destroy your Set Call of the Haunted, and you Chain it and target Daybreaker. You Special Summon your target and then the Typhoon destroys Call. You do NOT get Daybreaker’s effect because you Summoned him in the middle of a resolving Chain. You have to finish that Chain before youc an do anything else. What’s more, any optional “When” effect can only be activated “when” its trigger happens. If you’re doing something else, you have wait, so you miss your one chance to activate the effect.
But as it turns out, this rule can also apply to Quick Effects. The rules of YGO are made of a lot of different components, and many of them can be combined in a lot of different ways. Here’s an example of a Quick Effect “missing the timing”, as it were.
My opponent controls a face-up Maiden with Eyes of Blue in Attack Position. I control Changer Synchron and Jester Confit. I have Changer tune with Confit in order to Synchro Summon Formula Synchron. Changer Synchron’s effect is mandatory, so it automatically activates once the Synchro Summon is complete, and becomes Chain Link 1, and its target is Maiden. I also decide to activate Formula Synchron’s effect to let me draw one card. In this instance, Maiden with Eyes of Blue cannot activate her second effect. This is because it must activate “when” she is targeted by a card effect. She can’t do that, though, because the last thing to happen wasn’t her being targeted; it was Formula Synchron’s effect being activated. When the Chain resolves, I will draw one card and Changer Synchron will switch Maiden to face-up Defense Position. Maiden’s second effect will NOT activate, and my opponent will NOT Special Summon a Blue-Eyes White Dragon. (This, of course, means they can activate that effect later in the turn if the opportunity arises, or the Maiden’s effect to negate an attack.)
Here’s an example that might make a bit more sense to you. I control Stardust Dragon, and my opponent activates Card Destruction while they have two cards in hand and I have none. After resolving Card Destruction, my opponent activates the effects of the monsters they discarded: The Fabled Catsith and The Fabled Cerburrel. My opponent decides to put Catsith on Chain LInk 1, and Cerburrel on Chain Link 2. My Stardust Dragon cannot activate to negate Catsith’s effect. We have all been told that it’s because these effects have to be Chained directly to the effect they are negating, and while this is technically true, it doesn’t really explain why. It just repeats what we already knew in different words.
The reason Stardust cannot activate in the above Chain is because it missed its chance. Stardust Dragon can only activate its effect “When” a card-destroying effect or card is activated. The last thing to happen was NOT that, but was instead the activation of an effect that Special Summons a monster.
Just to drive it home, suppose my opponent put those effects on the Chain in reverse order: Cerburrel on Link 1, and Catsith on Link 2. NOW Stardust can activate to negate Catsith, because the last thing to happen is the activation of Catsith’s effect to destroy a card.
Funnily enough, the rules of “When” also apply to Counter Traps. In the above example, if The Fabled Cerburrel is on Chain Link 2, I could not activate the effect of Stardust Dragon, but I COULD activate the Counter Trap Solemn Warning. Conversely, if Cerburrel is on Chain Link 1, and The Fabled Catsith is on Chain Link 2, I can activate Stardust’s effect, but I CANNOT activate Solemn Warning against Cerburrel.
It’s a very simple principle to remember, really: If a card or effect that is optional can only activate “When [X event happens]”, then that event must be the LAST thing to happen, and that this rule applies to ALL cards, regardless of Spell Speed.