I have Mirror-Mad Phantasm in the graveyard and a copy it with Lazav, the Multifarious ability.
I then activate the Mirror-Mad Phantasm ability to shuffle and mill, with the intention of using the trick of card naming to mill the entire library, I know this interaction.
What I want to know is if I can choose to put Lazav, the Multifarious into the command zone, but still get the mill effect?
I know you can do this with tokens that don't actually get shuffled in, but I suspect its the action of doing it which triggers.
So the bit which throws me about sending to the commander zone, is that it specifically says "owner shuffles it into their library. If that player does ..".
I can choose to put Lazav, the Multifarious into the command zone, but still get the mill effect?
No.
614.6 If an event is replaced, it never happens. A modified event occurs instead, which may in turn trigger abilities. Note that the modified event may contain instructions that can’t be carried out, in which case the impossible instruction is simply ignored.
If a Commander would be put into a library, hand, graveyard or exile from anywhere, its owner may choose to move it to the command zone instead. Details
This is a replacement effect. It applies last and may apply multiple times to an event.
The creature never goes to the original destination zone and will not trigger abilities that trigger based on going there (e.g. "dies" triggers).
I have Mirror-Mad Phantasm in the graveyard and a copy it with Lazav, the Multifarious ability.
I then activate the Mirror-Mad Phantasm ability to shuffle and mill, with the intention of using the trick of card naming to mill the entire library, I know this interaction.
What I want to know is if I can choose to put Lazav, the Multifarious into the command zone, but still get the mill effect?
I know you can do this with tokens that don't actually get shuffled in, but I suspect its the action of doing it which triggers.
So the bit which throws me about sending to the commander zone, is that it specifically says "owner shuffles it into their library. If that player does ..".
I can choose to put Lazav, the Multifarious into the command zone, but still get the mill effect?
No. [...}
rezombied is incorrect; you will get the mill effect even if you put Lazav in the command zone. 614.6 has no bearing on this interaction. The rule you're looking for is this one, bolding mine:
117.12. Some spells, activated abilities, and triggered abilities read, "[Do something]. If [a player] [does, doesn't, or can't], [effect]." or "[A player] may [do something]. If [that player] [does, doesn't, or can't], [effect]." The action [do something] is a cost, paid when the spell or ability resolves. The "If [a player] [does, doesn't, or can't]" clause checks whether the player chose to pay an optional cost or started to pay a mandatory cost, regardless of what events actually occurred.
It doesn't matter that the event of shuffling Lazav in didn't happen, that's not actually what the ability is looking for. It only needs you to pay the mandatory cost of initiating the first action it tells you to do, which does happen even if the event that that cost causes is modified (otherwise there would be nothing removing Lazav from the battlefield and allowing you to put him in the command zone).
The "if you do" part is only there for the eventuality that the Phantasm would be removed from the battlefield before the ability resolves, then of course it doesn't work.
I'm a former judge (lapsed), who keeps up to date on rules and policy. Keep in mind that judges' answers aren't necessarily more valid than those of people who aren't judges; what matters is we can quote the rules to back up our answers. When in doubt, ask for such quotes.
Note that when the activated ability Lazav gained from Mirror-Mad Phantasm resolves, Lazav's owner shuffles their library "even if ... an effect", such as the effect imposed by C.R. 903.9b, "causes [Lazav] to be moved to another zone" (C.R. 701.19c, 201.4b).
EDIT (May 23): Edited.
EDIT (Jul. 2, 2020): Edited to conform to rule update with Core Set 2021.
Of course, for this particular interaction, even if you did have to put Lazav in the library in order for it to work it wouldn't matter; you're milling your entire library, including the Lazav you shuffled in, at which point you would again have the option of putting him in your command zone.
I then activate the Mirror-Mad Phantasm ability to shuffle and mill, with the intention of using the trick of card naming to mill the entire library, I know this interaction.
What I want to know is if I can choose to put Lazav, the Multifarious into the command zone, but still get the mill effect?
I know you can do this with tokens that don't actually get shuffled in, but I suspect its the action of doing it which triggers.
So the bit which throws me about sending to the commander zone, is that it specifically says "owner shuffles it into their library. If that player does ..".
Anybody know the official interaction?
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Feather, the Redeemed
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-Prime Speaker Vannifar
---------------------Will & Rowan Kenrith
No.
614.6 If an event is replaced, it never happens. A modified event occurs instead, which may in turn trigger abilities. Note that the modified event may contain instructions that can’t be carried out, in which case the impossible instruction is simply ignored.
The "if you do" part is only there for the eventuality that the Phantasm would be removed from the battlefield before the ability resolves, then of course it doesn't work.
EDIT (May 23): Edited.
EDIT (Jul. 2, 2020): Edited to conform to rule update with Core Set 2021.
Two Score, Minus Two or: A Stargate Tail
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